$NTRS
NORTHERN TRUST CORP Stock $ntrs

$ntrs Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000007312424000073 Filed on February 27, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$1.647B	$1.545B	$6.774B
YoY Change	54.83%	1.73%	0.18%
Cost Of Revenue	$1.729B	$1.520B	$4.483B
YoY Change	139.9%	204.89%	516.18%
Gross Profit	$1.647B	$1.545B	$6.774B
YoY Change	-5.61%	1.73%	0.18%
Gross Profit Margin	100.0%	100.0%	100.0%
Selling, General & Admin	$1.035B	$976.5M	$3.905B
YoY Change	2.15%	-0.66%	4.31%
% of Gross Profit	62.85%	63.19%	57.65%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$170.3M	$169.0M	$634.6M
YoY Change	9.94%	14.04%	14.63%
% of Gross Profit	10.34%	10.94%	9.37%
Operating Expenses	$1.344B	$1.315B	$5.224B
YoY Change	3.31%	-1.03%	4.59%
Operating Profit	$303.1M	$230.4M	$1.549B
YoY Change	-31.73%	21.01%	-12.28%
Interest Expense	$1.918B		$5.343B
YoY Change	107.48%		439.42%
% of Operating Profit	632.63%		344.84%
Other Income/Expense, Net
YoY Change
Pretax Income	$290.6M	$145.8M	$1.465B
YoY Change	-34.55%	-23.42%	-17.07%
Income Tax	$75.90M	$32.70M	$357.5M
% Of Pretax Income	26.12%	22.43%	24.41%
Net Earnings	$196.1M	$106.5M	$1.054B
YoY Change	-41.39%	-28.38%	-17.82%
Net Earnings / Revenue	11.91%	6.89%	15.56%
Basic Earnings Per Share	$0.96		$5.09
Diluted Earnings Per Share	$0.96	$0.52	$5.08
COMMON SHARES
Basic Shares Outstanding	204.8M shares		207.2M shares
Diluted Shares Outstanding	205.1M shares		207.6M shares

Balance Sheet

Concept	2024 Q1	2023 Q4	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments	$4.636B	$4.668B	$4.668B
YoY Change	-91.44%	33.13%	33.13%
Cash & Equivalents	$2.601B	$3.134B	$3.134B
Short-Term Investments	$49.14B	$49.31B
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets	$4.636B	$4.668B	$4.668B
YoY Change	-3.94%	33.13%	33.13%
LONG-TERM ASSETS
Property, Plant & Equipment	$488.0M	$502.2M	$502.2M
YoY Change	1.35%	0.34%	0.34%
Goodwill	$697.5M	$702.3M
YoY Change	0.35%	1.59%
Intangibles
YoY Change
Long-Term Investments	$94.55B	$89.62B	$89.62B
YoY Change	3.59%	-8.39%	-8.39%
Other Assets
YoY Change
Total Long-Term Assets	$151.5B	$146.1B	$146.1B
YoY Change	3.55%	-3.57%	-3.57%
TOTAL ASSETS
Total Short-Term Assets	$4.636B	$4.668B	$4.668B
Total Long-Term Assets	$151.5B	$146.1B	$146.1B
Total Assets	$156.1B	$150.8B	$150.8B
YoY Change	3.31%	-2.74%	-2.74%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses		$692.8M	$692.8M
YoY Change		10.64%	10.64%
Deferred Revenue
YoY Change
Short-Term Debt	$127.1B	$120.0B	$120.0B
YoY Change	7.15%	-5.07%	-5.07%
Long-Term Debt Due	$6.526B	$6.568B	$6.568B
YoY Change	-42.58%	-13.49%	-13.49%
Total Short-Term Liabilities	$133.6B	$126.6B	$126.6B
YoY Change	2.8%	-5.54%	-5.54%
LONG-TERM LIABILITIES
Long-Term Debt	$6.813B	$6.838B	$6.838B
YoY Change	40.75%	42.75%	42.75%
Other Long-Term Liabilities	$3.617B	$5.485B	$5.485B
YoY Change	-23.65%	9.74%	9.74%
Total Long-Term Liabilities	$10.43B	$12.32B	$12.32B
YoY Change	8.89%	25.89%	25.89%
TOTAL LIABILITIES
Total Short-Term Liabilities	$133.6B	$126.6B	$126.6B
Total Long-Term Liabilities	$10.43B	$12.32B	$12.32B
Total Liabilities	$144.0B	$138.9B	$138.9B
YoY Change	3.22%	-3.4%	-3.4%
SHAREHOLDERS EQUITY
Retained Earnings	$14.28B	$14.23B
YoY Change	2.3%	3.15%
Common Stock	$408.6M	$408.6M
YoY Change	0.0%	0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$3.537B	$3.501B
YoY Change	8.41%	7.83%
Treasury Stock Shares
Shareholders Equity	$12.10B	$11.90B	$11.90B
YoY Change
Total Liabilities & Shareholders Equity	$156.1B	$150.8B	$150.8B
YoY Change	3.31%	-2.74%	-2.74%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$196.1M	$106.5M	$1.054B
YoY Change	-41.39%	-28.38%	-17.82%
Depreciation, Depletion And Amortization	$170.3M	$169.0M	$634.6M
YoY Change	9.94%	14.04%	14.63%
Cash From Operating Activities	-$1.453B	$2.803B	$2.626B
YoY Change	780.9%	-32.49%	9.75%
INVESTING ACTIVITIES
Capital Expenditures	$14.30M	$210.3M	$116.5M
YoY Change	24.35%	-7.6%	-9.41%
Acquisitions
YoY Change
Other Investing Activities	-$653.6M	-$4.653B	$1.539B
YoY Change	-432.62%	-206.13%	381.99%
Cash From Investing Activities	-$4.793B	-$4.863B	$4.784B
YoY Change	-197.44%	-217.0%	-81.55%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	$6.936B	1.708B	-$7.183B
YoY Change	-250.86%	-120.63%	-72.83%
NET CHANGE
Cash From Operating Activities	-$1.453B	2.803B	$2.626B
Cash From Investing Activities	-$4.793B	-4.863B	$4.784B
Cash From Financing Activities	$6.936B	1.708B	-$7.183B
Net Change In Cash	$517.2M	-351.7M	$137.3M
YoY Change	201.22%	-1369.68%	-91.4%
FREE CASH FLOW
Cash From Operating Activities	-$1.453B	$2.803B	$2.626B
Capital Expenditures	$14.30M	$210.3M	$116.5M
Free Cash Flow	-$1.467B	$2.593B	$2.509B
YoY Change	731.58%	-33.93%	10.84%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2022	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	191300000	usd
CY2021	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	243900000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-169500000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-214000000.0	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-300000	usd
CY2022	us-gaap	Noninterest Income NoninterestIncome	4874000000	usd
CY2021	us-gaap	Noninterest Income NoninterestIncome	5081800000	usd
CY2021	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	1406500000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	4791500000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	4654200000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	7500000	usd
CY2023	dei	Amendment Flag AmendmentFlag	false
CY2023	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2023
CY2023	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2023	dei	Entity Central Index Key EntityCentralIndexKey	0000073124
CY2023Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.6667
CY2022Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.6667
CY2023Q4	us-gaap	Derivative Asset Statement Of Financial Position Extensible Enumeration DerivativeAssetStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#OtherAssets
CY2022Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	22879300000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	26221700000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	25036100000	usd
CY2023Q4	us-gaap	Trading Securities TradingSecurities	0	usd
CY2023Q4	us-gaap	Derivative Liability Statement Of Financial Position Extensible Enumeration DerivativeLiabilityStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#OtherLiabilities
CY2022Q4	us-gaap	Derivative Asset Statement Of Financial Position Extensible Enumeration DerivativeAssetStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#OtherAssets
CY2022Q4	us-gaap	Derivative Liability Statement Of Financial Position Extensible Enumeration DerivativeLiabilityStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#OtherLiabilities
CY2022Q4	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List FinancingReceivableAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2023Q4	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List FinancingReceivableAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2023Q4	us-gaap	Debt Securities Held To Maturity Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2022Q4	us-gaap	Debt Securities Held To Maturity Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2022Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2023Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss Statement Of Financial Position Extensible List DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2022Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilities
CY2023Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilities
CY2022Q4	us-gaap	Hedged Asset Statement Of Financial Position Extensible Enumeration HedgedAssetStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#DebtSecuritiesAvailableForSaleExcludingAccruedInterest
CY2023Q4	us-gaap	Hedged Asset Statement Of Financial Position Extensible Enumeration HedgedAssetStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#DebtSecuritiesAvailableForSaleExcludingAccruedInterest
CY2022Q4	us-gaap	Hedged Liability Statement Of Financial Position Extensible Enumeration HedgedLiabilityStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#SeniorNotes http://www.northerntrust.com/20231231#SubordinatedDebtAndLongTermFederalHomeLoanBankAdvances
CY2023Q4	us-gaap	Hedged Liability Statement Of Financial Position Extensible Enumeration HedgedLiabilityStatementOfFinancialPositionExtensibleEnumeration	http://fasb.org/us-gaap/2023#SeniorNotes http://www.northerntrust.com/20231231#SubordinatedDebtAndLongTermFederalHomeLoanBankAdvances
CY2023	dei	Document Annual Report DocumentAnnualReport	true
CY2023	dei	Document Period End Date DocumentPeriodEndDate	2023-12-31
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2023	dei	Document Transition Report DocumentTransitionReport	false
CY2023	dei	Entity File Number EntityFileNumber	001-36609
CY2023	dei	Entity Registrant Name EntityRegistrantName	NORTHERN TRUST CORPORATION
CY2023	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2023	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	36-2723087
CY2023	dei	Entity Address Address Line1 EntityAddressAddressLine1	50 South La Salle Street
CY2023	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	60603
CY2023	dei	City Area Code CityAreaCode	312
CY2023	dei	Local Phone Number LocalPhoneNumber	630-6000
CY2023	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2023	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2023	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2023	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2023	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2023	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2023	dei	Entity Small Business EntitySmallBusiness	false
CY2023	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2023	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2023	dei	Entity Shell Company EntityShellCompany	false
CY2023Q2	dei	Entity Public Float EntityPublicFloat	15300000000	usd
CY2024Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	204841515	shares
CY2023Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	4791500000	usd
CY2022Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	4654200000	usd
CY2023Q4	ntrs	Federal Reserve And Foreign Central Bank Deposits FederalReserveAndForeignCentralBankDeposits	34326200000	usd
CY2022Q4	ntrs	Federal Reserve And Foreign Central Bank Deposits FederalReserveAndForeignCentralBankDeposits	40030400000	usd
CY2023Q4	us-gaap	Interest Bearing Deposits In Banks InterestBearingDepositsInBanks	1939000000	usd
CY2022Q4	us-gaap	Interest Bearing Deposits In Banks InterestBearingDepositsInBanks	1941100000	usd
CY2023Q4	us-gaap	Federal Funds Sold FederalFundsSold	0	usd
CY2022Q4	us-gaap	Federal Funds Sold FederalFundsSold	32000000.0	usd
CY2023Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	784700000	usd
CY2022Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	1070300000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	23659000000	usd
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CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	500500000	usd
CY2023Q4	ntrs	Client Security Settlement Receivables ClientSecuritySettlementReceivables	212600000	usd
CY2022Q4	ntrs	Client Security Settlement Receivables ClientSecuritySettlementReceivables	1698300000	usd
CY2023Q4	us-gaap	Goodwill Goodwill	702300000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	691300000	usd
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CY2023Q4	us-gaap	Treasury Stock Value TreasuryStockValue	3501100000	usd
CY2022Q4	us-gaap	Treasury Stock Value TreasuryStockValue	3246800000	usd
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CY2023Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	150783100000	usd
CY2022Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	155036700000	usd
CY2023	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4361800000	usd
CY2022	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4432600000	usd
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4361100000	usd
CY2023	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	203900000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	288600000	usd
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	292600000	usd
CY2023	ntrs	Treasury Management Fees TreasuryManagementFees	31600000	usd
CY2022	ntrs	Treasury Management Fees TreasuryManagementFees	39300000	usd
CY2021	ntrs	Treasury Management Fees TreasuryManagementFees	44300000	usd
CY2023	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	135000000.0	usd
CY2022	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	136200000	usd
CY2021	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	140200000	usd
CY2023	us-gaap	Interest Expense InterestExpense	5343000000	usd
CY2022	us-gaap	Interest Expense InterestExpense	990500000	usd
CY2021	us-gaap	Interest Expense InterestExpense	23800000	usd
CY2023	ntrs	Credit Loss Expense Reversal And Available For Sale Allowance For Credit Loss CreditLossExpenseReversalAndAvailableForSaleAllowanceForCreditLoss	24500000	usd
CY2023	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	1957500000	usd
CY2022	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	1875200000	usd
CY2023	ntrs	Salaries Wages And Incentives SalariesWagesAndIncentives	2321800000	usd
CY2022	ntrs	Salaries Wages And Incentives SalariesWagesAndIncentives	2248000000	usd
CY2021	ntrs	Salaries Wages And Incentives SalariesWagesAndIncentives	2011000000	usd
CY2023	ntrs	Defined Benefit Plan Benefit Obligation Increase Decrease For Amortization Period Adjustment DefinedBenefitPlanBenefitObligationIncreaseDecreaseForAmortizationPeriodAdjustment	405200000	usd
CY2022	ntrs	Defined Benefit Plan Benefit Obligation Increase Decrease For Amortization Period Adjustment DefinedBenefitPlanBenefitObligationIncreaseDecreaseForAmortizationPeriodAdjustment	437400000	usd
CY2021	ntrs	Defined Benefit Plan Benefit Obligation Increase Decrease For Amortization Period Adjustment DefinedBenefitPlanBenefitObligationIncreaseDecreaseForAmortizationPeriodAdjustment	431400000	usd
CY2023	us-gaap	Professional Fees ProfessionalFees	906500000	usd
CY2022	us-gaap	Professional Fees ProfessionalFees	880300000	usd
CY2021	us-gaap	Professional Fees ProfessionalFees	849400000	usd
CY2023	ntrs	Equipment And Software Expense EquipmentAndSoftwareExpense	945500000	usd
CY2022	ntrs	Equipment And Software Expense EquipmentAndSoftwareExpense	838800000	usd
CY2021	ntrs	Equipment And Software Expense EquipmentAndSoftwareExpense	736300000	usd
CY2023	us-gaap	Occupancy Net OccupancyNet	232300000	usd
CY2022	us-gaap	Occupancy Net OccupancyNet	219100000	usd
CY2021	us-gaap	Occupancy Net OccupancyNet	208700000	usd
CY2023	us-gaap	Other Noninterest Expense OtherNoninterestExpense	472900000	usd
CY2022	us-gaap	Other Noninterest Expense OtherNoninterestExpense	359300000	usd
CY2021	us-gaap	Other Noninterest Expense OtherNoninterestExpense	299100000	usd
CY2023	us-gaap	Noninterest Expense NoninterestExpense	5284200000	usd
CY2022	us-gaap	Noninterest Expense NoninterestExpense	4982900000	usd
CY2021	us-gaap	Noninterest Expense NoninterestExpense	4535900000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1464800000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1766300000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	2010100000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	357500000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	430300000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	464800000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	1107300000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1336000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1545300000	usd
CY2023	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41800000	usd
CY2022	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41800000	usd
CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41800000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1065500000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1294200000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1503500000	usd
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.09
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.16
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	7.16
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.08
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.14
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	7.14
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	207248094	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	208309331	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	208075522	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	207563746	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	208867264	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	208899230	shares
CY2023	us-gaap	Net Income Loss NetIncomeLoss	1107300000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1336000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1545300000	usd
CY2023	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	443700000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-1474700000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-534700000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-400000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	3600000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	800000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	39000000.0	usd
CY2022	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	9400000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	10500000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	51000000.0	usd
CY2022	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	71900000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-59800000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	431300000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1533600000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1538600000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-197600000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1081700000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	11688300000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1545300000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-463600000	usd
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.80
CY2021	us-gaap	Dividends Common Stock DividendsCommonStock	593900000	usd
CY2021	us-gaap	Dividends Preferred Stock DividendsPreferredStock	41800000	usd
CY2021	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	150100000	usd
CY2021	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	267600000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	12016800000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1336000000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1533600000	usd
CY2022	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.90
CY2022	us-gaap	Dividends Common Stock DividendsCommonStock	613000000.0	usd
CY2022	us-gaap	Dividends Preferred Stock DividendsPreferredStock	41800000	usd
CY2022	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	130500000	usd
CY2022	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	35400000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	11259500000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	1107300000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	431300000	usd
CY2023	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	3.00
CY2023	us-gaap	Dividends Common Stock DividendsCommonStock	630200000	usd
CY2023	us-gaap	Dividends Preferred Stock DividendsPreferredStock	41800000	usd
CY2023	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	121800000	usd
CY2023	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	347500000	usd
CY2023	ntrs	Share Repurchase Program Excise Tax ShareRepurchaseProgramExciseTax	2500000	usd
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	11897900000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	1107300000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1336000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1545300000	usd
CY2023	us-gaap	Gain Loss On Investments GainLossOnInvestments	-169500000	usd
CY2022	us-gaap	Gain Loss On Investments GainLossOnInvestments	-1100000	usd
CY2021	us-gaap	Gain Loss On Investments GainLossOnInvestments	-300000	usd
CY2023	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-3000000.0	usd
CY2022	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-59200000	usd
CY2021	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-99700000	usd
CY2023	ntrs	Credit Loss Expense Reversal And Available For Sale Allowance For Credit Loss CreditLossExpenseReversalAndAvailableForSaleAllowanceForCreditLoss	24500000	usd
CY2022	ntrs	Credit Loss Expense Reversal And Available For Sale Allowance For Credit Loss CreditLossExpenseReversalAndAvailableForSaleAllowanceForCreditLoss	12000000.0	usd
CY2021	ntrs	Credit Loss Expense Reversal And Available For Sale Allowance For Credit Loss CreditLossExpenseReversalAndAvailableForSaleAllowanceForCreditLoss	-81500000	usd
CY2023	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	634600000	usd
CY2022	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	553600000	usd
CY2021	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	515600000	usd
CY2023	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-44400000	usd
CY2022	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	61300000	usd
CY2021	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	37200000	usd
CY2023	us-gaap	Pension Contributions PensionContributions	20400000	usd
CY2022	us-gaap	Pension Contributions PensionContributions	24300000	usd
CY2021	us-gaap	Pension Contributions PensionContributions	11200000	usd
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-48200000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-142700000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	2000000.0	usd
CY2023	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-12000000.0	usd
CY2022	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-57900000	usd
CY2021	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	460900000	usd
CY2023	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	85800000	usd
CY2022	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	172600000	usd
CY2021	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-7800000	usd
CY2023	us-gaap	Increase Decrease In Derivative Assets IncreaseDecreaseInDerivativeAssets	72600000	usd
CY2022	us-gaap	Increase Decrease In Derivative Assets IncreaseDecreaseInDerivativeAssets	-639400000	usd
CY2021	us-gaap	Increase Decrease In Derivative Assets IncreaseDecreaseInDerivativeAssets	466500000	usd
CY2023	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-774500000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	333700000	usd
CY2021	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-183800000	usd
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2625600000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2392400000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1356000000	usd
CY2023	ntrs	Proceeds From Payments For Federal Funds Sold ProceedsFromPaymentsForFederalFundsSold	32000000.0	usd
CY2022	ntrs	Proceeds From Payments For Federal Funds Sold ProceedsFromPaymentsForFederalFundsSold	-32000000.0	usd
CY2021	ntrs	Proceeds From Payments For Federal Funds Sold ProceedsFromPaymentsForFederalFundsSold	0	usd
CY2023	us-gaap	Proceeds From Payments For Securities Purchased Under Agreements To Resell ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell	285400000	usd
CY2022	us-gaap	Proceeds From Payments For Securities Purchased Under Agreements To Resell ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell	-419000000.0	usd
CY2021	us-gaap	Proceeds From Payments For Securities Purchased Under Agreements To Resell ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell	897700000	usd
CY2023	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	28500000	usd
CY2022	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	-158900000	usd
CY2021	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	2344500000	usd
CY2023	ntrs	Payments For Proceeds From Federal Reserve And Foreign Central Bank Deposits PaymentsForProceedsFromFederalReserveAndForeignCentralBankDeposits	-6205900000	usd
CY2022	ntrs	Payments For Proceeds From Federal Reserve And Foreign Central Bank Deposits PaymentsForProceedsFromFederalReserveAndForeignCentralBankDeposits	-23483800000	usd
CY2021	ntrs	Payments For Proceeds From Federal Reserve And Foreign Central Bank Deposits PaymentsForProceedsFromFederalReserveAndForeignCentralBankDeposits	9970400000	usd
CY2023	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	32773900000	usd
CY2022	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	32830800000	usd
CY2021	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	54734900000	usd
CY2023	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	32123000000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	37667800000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	54902600000	usd
CY2023	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	7320200000	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	4567700000	usd
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	13896200000	usd
CY2023	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	11614800000	usd
CY2022	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	6513000000	usd
CY2021	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	10079000000	usd
CY2023	us-gaap	Payments For Proceeds From Loans Receivable PaymentsForProceedsFromLoansReceivable	4702100000	usd
CY2022	us-gaap	Payments For Proceeds From Loans Receivable PaymentsForProceedsFromLoansReceivable	2441600000	usd
CY2021	us-gaap	Payments For Proceeds From Loans Receivable PaymentsForProceedsFromLoansReceivable	6744700000	usd
CY2023	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	116500000	usd
CY2022	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	128600000	usd
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	95500000	usd
CY2023	us-gaap	Payments For Software PaymentsForSoftware	559300000	usd
CY2022	us-gaap	Payments For Software PaymentsForSoftware	594900000	usd
CY2021	us-gaap	Payments For Software PaymentsForSoftware	419600000	usd
CY2023	ntrs	Net Change In Client Security Settlement Receivables NetChangeInClientSecuritySettlementReceivables	-1505500000	usd
CY2022	ntrs	Net Change In Client Security Settlement Receivables NetChangeInClientSecuritySettlementReceivables	-258000000.0	usd
CY2021	ntrs	Net Change In Client Security Settlement Receivables NetChangeInClientSecuritySettlementReceivables	801400000	usd
CY2023	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	usd
CY2022	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	500000000.0	usd
CY2021	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	usd
CY2023	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	1539000000	usd
CY2022	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	319300000	usd
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	163700000	usd
CY2023	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	4784100000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	25929800000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-18602600000	usd
CY2023	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-8478400000	usd
CY2022	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-32996900000	usd
CY2021	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	17885500000	usd
CY2023	ntrs	Change In Federal Funds Purchased ChangeInFederalFundsPurchased	-1148600000	usd
CY2022	ntrs	Change In Federal Funds Purchased ChangeInFederalFundsPurchased	-1896700000	usd
CY2021	ntrs	Change In Federal Funds Purchased ChangeInFederalFundsPurchased	260000000.0	usd
CY2023	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	217500000	usd
CY2022	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	35300000	usd
CY2021	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	492100000	usd
CY2023	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	-1059100000	usd
CY2022	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	3966900000	usd
CY2021	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	-426500000	usd
CY2023	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	2000000000	usd
CY2022	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	usd
CY2021	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	usd
CY2023	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	0	usd
CY2022	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	1988800000	usd
CY2021	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	0	usd
CY2023	us-gaap	Repayments Of Senior Debt RepaymentsOfSeniorDebt	0	usd
CY2022	us-gaap	Repayments Of Senior Debt RepaymentsOfSeniorDebt	500000000.0	usd
CY2021	us-gaap	Repayments Of Senior Debt RepaymentsOfSeniorDebt	500000000.0	usd
CY2023	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	0	usd
CY2022	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	0	usd
CY2021	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	278800000	usd
CY2023	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	347500000	usd
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	35400000	usd
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	267600000	usd
CY2023	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	2300000	usd
CY2022	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	3900000	usd
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	53800000	usd
CY2023	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	621500000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	750200000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	583300000	usd
CY2023	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	41800000	usd
CY2022	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	46500000	usd
CY2021	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	41800000	usd
CY2023	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2700000	usd
CY2022	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	0	usd
CY2021	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	100000	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-7182600000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-26437400000	usd
CY2023	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-89800000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-1332700000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	3056800000	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	5285500000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	822400000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	30800000	usd
CY2023	us-gaap	Income Taxes Paid IncomeTaxesPaid	362500000	usd
CY2022	us-gaap	Income Taxes Paid IncomeTaxesPaid	459900000	usd
CY2021	us-gaap	Income Taxes Paid IncomeTaxesPaid	371000000.0	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	544200000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	19435300000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	568300000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	1200000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	15665400000	usd
CY2023	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	200000	usd
CY2022	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	0	usd
CY2021	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	12900000	usd
CY2023	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	0	usd
CY2022	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	6623300000	usd
CY2021	us-gaap	Debt Securities Held To Maturity Transfer Amount DebtSecuritiesHeldToMaturityTransferAmount	6864100000	usd
CY2023	ntrs	Numberof Client Focused Reportable Segment NumberofClientFocusedReportableSegment	2	segment
CY2023	us-gaap	Use Of Estimates UseOfEstimates	Use of Estimates in the Preparation of Financial Statements.<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions in the application of certain of our significant accounting policies that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expense during the reporting period. Actual results could differ from those estimates.</span>
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	727700000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	23659000000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	13200000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	582400000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	23089800000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	27760000000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	7700000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1067800000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	26699900000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	3386300000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	3343800000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	15718300000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	15307000000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	3840700000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	3752400000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	713700000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	686600000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss	23659000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Excluding Accrued Interest DebtSecuritiesAvailableForSaleExcludingAccruedInterest	23089800000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	503000000.0	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	24100000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	18932300000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	5769400000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	321500000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	21434800000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	1049200000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	1300000	usd
CY2023Q4	ntrs	Number Of Securities Unrealized Losses Position NumberOfSecuritiesUnrealizedLossesPosition	898	investment
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	19400000000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	568300000	usd
CY2022Q4	ntrs	Number Of Securities Unrealized Losses Position NumberOfSecuritiesUnrealizedLossesPosition	1030	investment
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	21400000000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	1000000000	usd
CY2023Q1	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	6900000	usd
	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	-176400000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	1200000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	1300000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	26221700000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	6900000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	1755600000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	24473000000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	25036100000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	1400000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	2158200000	usd
CY2022Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	22879300000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	26200000000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	25000000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date Year One DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateYearOne	6756600000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	6618000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year One Through Five DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive	12455800000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	11607200000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year5 Through10 DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear5Through10	4798300000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	4380700000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Amortized Cost Excluding Accrued Interest After Allowance For Credit Loss Maturity Allocated And Single Maturity Date After Year10 DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear10	2211000000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	1867100000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	26221700000	usd
CY2023Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	24473000000	usd
CY2022	ntrs	Held To Maturity Securities Transferred From Available For Sale HeldToMaturitySecuritiesTransferredFromAvailableForSale	6600000000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	26221700000	usd
CY2023Q4	ntrs	Debt Securities Held To Maturity Percent Of Portfolio DebtSecuritiesHeldToMaturityPercentOfPortfolio	1
CY2022Q4	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Before Allowance For Credit Loss DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLoss	25036100000	usd
CY2022Q4	ntrs	Debt Securities Held To Maturity Percent Of Portfolio DebtSecuritiesHeldToMaturityPercentOfPortfolio	1
CY2023Q4	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-176400000	usd
CY2023Q1	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	6900000	usd
CY2022	ntrs	Proceeds From Sale Of Investment Securities ProceedsFromSaleOfInvestmentSecurities	138700000	usd
CY2021	ntrs	Proceeds From Sale Of Investment Securities ProceedsFromSaleOfInvestmentSecurities	116700000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	10500000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	0	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	1400000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	180000000.0	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	214000000.0	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	1700000	usd
CY2023	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-169500000	usd
CY2022	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-214000000.0	usd
CY2021	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-300000	usd
CY2022	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-214000000	usd
CY2023	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-169500000	usd
CY2022	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-214000000.0	usd
CY2021	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-300000	usd
CY2022	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-214000000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	47617000000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	42893300000	usd
CY2023	ntrs	Line Of Credit Draw Down Period LineOfCreditDrawDownPeriod	P10Y
CY2023Q4	ntrs	Loans Receivable Overdraft Advances LoansReceivableOverdraftAdvances	8400000000	usd
CY2022Q4	ntrs	Loans Receivable Overdraft Advances LoansReceivableOverdraftAdvances	2900000000	usd
CY2023Q4	ntrs	Loans Receivable Overdraft Advances LoansReceivableOverdraftAdvances	8400000000	usd
CY2023Q4	ntrs	Overdrawn Demand Deposit Accounts OverdrawnDemandDepositAccounts	12100000	usd
CY2022Q4	ntrs	Overdrawn Demand Deposit Accounts OverdrawnDemandDepositAccounts	24400000	usd
CY2023Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	0	usd
CY2022Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	0	usd
CY2023	us-gaap	Loan Processing Fee LoanProcessingFee	2500000	usd
CY2022	us-gaap	Loan Processing Fee LoanProcessingFee	11200000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	13006400000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	4823900000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	4177600000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	1765400000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	1208700000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	2681500000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Revolving FinancingReceivableExcludingAccruedInterestRevolving	19233500000	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Converted To Term Loan FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan	720000000.0	usd
CY2023Q4	us-gaap	Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss	47617000000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff	2100000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff	4400000	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff	0	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff	0	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff	0	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year Writeoff FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff	1000000.0	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Writeoff FinancingReceivableExcludingAccruedInterestRevolvingWriteoff	0	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Revolving Converted To Term Loan Writeoff FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoanWriteoff	0	usd
CY2023	us-gaap	Financing Receivable Excluding Accrued Interest Allowance For Credit Loss Writeoff FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff	7500000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year One Originated Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear	7905600000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Two Originated Fiscal Year Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear	5484100000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Three Originated Two Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear	2791400000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Four Originated Three Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear	2007300000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Year Five Originated Four Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear	746100000	usd
CY2022Q4	us-gaap	Financing Receivable Excluding Accrued Interest Originated More Than Five Years Before Current Fiscal Year FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear	3012100000	usd
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CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Loss Excluding Accrued Interest FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest	144300000	usd
CY2023Q4	ntrs	Off Balance Sheet Credit Loss Liability Individually Evaluated For Impairment OffBalanceSheetCreditLossLiabilityIndividuallyEvaluatedForImpairment	0	usd
CY2022Q4	ntrs	Off Balance Sheet Credit Loss Liability Individually Evaluated For Impairment OffBalanceSheetCreditLossLiabilityIndividuallyEvaluatedForImpairment	0	usd
CY2023Q4	ntrs	Off Balance Sheet Credit Loss Liability Collectively Evaluated For Impairment OffBalanceSheetCreditLossLiabilityCollectivelyEvaluatedForImpairment	26900000	usd
CY2022Q4	ntrs	Off Balance Sheet Credit Loss Liability Collectively Evaluated For Impairment OffBalanceSheetCreditLossLiabilityCollectivelyEvaluatedForImpairment	38500000	usd
CY2023Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	26900000	usd
CY2022Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	38500000	usd
CY2023Q4	ntrs	Financing Receivable Allowance For Credit Losses And Off Balance Sheet Credit Loss Liability FinancingReceivableAllowanceForCreditLossesAndOffBalanceSheetCreditLossLiability	205600000	usd
CY2022Q4	ntrs	Financing Receivable Allowance For Credit Losses And Off Balance Sheet Credit Loss Liability FinancingReceivableAllowanceForCreditLossesAndOffBalanceSheetCreditLossLiability	182800000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	16000000.0	usd
CY2023	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossWriteoff	1200000	usd
CY2023	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Recovery DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossRecovery	0	usd
CY2023	ntrs	Debt Securities Held To Maturity Excluding Accrued Interest Allowance For Credit Loss Writeoff Recovery DebtSecuritiesHeldToMaturityExcludingAccruedInterestAllowanceForCreditLossWriteoffRecovery	1200000	usd
CY2023	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	-2100000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	12700000	usd
CY2021Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	11200000	usd
CY2022	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	4800000	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	16000000.0	usd
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	7300000	usd
CY2021	us-gaap	Debt Securities Held To Maturity Excluding Accrued Interest Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal	3900000	usd
CY2021Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest	11200000	usd
CY2023Q4	ntrs	Other Financial Assets Allowance For Credit Loss Excluding Accrued Interest OtherFinancialAssetsAllowanceForCreditLossExcludingAccruedInterest	900000	usd
CY2022Q4	ntrs	Other Financial Assets Allowance For Credit Loss Excluding Accrued Interest OtherFinancialAssetsAllowanceForCreditLossExcludingAccruedInterest	800000	usd
CY2023Q4	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss	241700000	usd
CY2022Q4	us-gaap	Financing Receivable Accrued Interest After Allowance For Credit Loss FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss	203100000	usd
CY2023Q4	us-gaap	Debt Securities Held To Maturity Accrued Interest After Allowance For Credit Loss DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss	72000000.0	usd
CY2022Q4	us-gaap	Debt Securities Held To Maturity Accrued Interest After Allowance For Credit Loss DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss	63200000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	129200000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Accrued Interest After Allowance For Credit Loss DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss	147100000	usd
CY2023Q4	ntrs	Other Financial Assets Accrued Interest After Allowance For Credit Loss OtherFinancialAssetsAccruedInterestAfterAllowanceForCreditLoss	86000000.0	usd
CY2022Q4	ntrs	Other Financial Assets Accrued Interest After Allowance For Credit Loss OtherFinancialAssetsAccruedInterestAfterAllowanceForCreditLoss	43800000	usd
CY2023Q4	us-gaap	Interest Receivable InterestReceivable	528900000	usd
CY2022Q4	us-gaap	Interest Receivable InterestReceivable	457200000	usd
CY2023Q4	ntrs	Credit Risk To Banks Non Interest Bearing Balances Held At Banks CreditRiskToBanksNonInterestBearingBalancesHeldAtBanks	1900000000	usd
CY2023Q4	ntrs	Credit Risk To Banks CreditRiskToBanks	4700000000	usd
CY2023Q4	us-gaap	Federal Funds Sold And Securities Purchased Under Agreements To Resell FederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell	800000000	usd
CY2022Q4	ntrs	Credit Risk To Banks Non Interest Bearing Balances Held At Banks CreditRiskToBanksNonInterestBearingBalancesHeldAtBanks	1900000000	usd
CY2022Q4	ntrs	Credit Risk To Banks CreditRiskToBanks	4600000000	usd
CY2022Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	1100000000	usd
CY2023Q4	ntrs	Residential Real Estate Loans Percentage Of Total Us Loansand Leases ResidentialRealEstateLoansPercentageOfTotalUSLoansandLeases	0.14
CY2022Q4	ntrs	Residential Real Estate Loans Percentage Of Total Us Loansand Leases ResidentialRealEstateLoansPercentageOfTotalUSLoansandLeases	0.16
CY2023Q4	ntrs	Loans And Leases Receivable Residential Real Estate LoansAndLeasesReceivableResidentialRealEstate	6327100000	usd
CY2022Q4	ntrs	Loans And Leases Receivable Residential Real Estate LoansAndLeasesReceivableResidentialRealEstate	6413500000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1331100000	usd
CY2023Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	828900000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	502200000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	1250000000	usd
CY2022Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	749500000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	500500000	usd
CY2023	us-gaap	Depreciation Nonproduction DepreciationNonproduction	115900000	usd
CY2022	us-gaap	Depreciation Nonproduction DepreciationNonproduction	110100000	usd
CY2021	us-gaap	Depreciation Nonproduction DepreciationNonproduction	110800000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	109200000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	104500000	usd
CY2023	us-gaap	Variable Lease Cost VariableLeaseCost	54700000	usd
CY2022	us-gaap	Variable Lease Cost VariableLeaseCost	82200000	usd
CY2023	us-gaap	Sublease Income SubleaseIncome	2700000	usd
CY2022	us-gaap	Sublease Income SubleaseIncome	2900000	usd
CY2023	us-gaap	Lease Cost LeaseCost	161200000	usd
CY2022	us-gaap	Lease Cost LeaseCost	183800000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	93200000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	100300000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	85500000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	84900000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	72800000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	393500000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	830200000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	137400000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	692800000	usd
CY2023Q4	ntrs	Lessee Operating Lease Lease Notyet Commenced Liability LesseeOperatingLeaseLeaseNotyetCommencedLiability	0	usd
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	522800000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	484800000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	692800000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	626200000	usd
CY2023Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y1M6D
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y3M18D
CY2023Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.033
CY2022Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.030
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	91400000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	70300000	usd
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	122600000	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	61000000.0	usd
CY2021Q4	us-gaap	Goodwill Goodwill	706200000	usd
CY2022	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-14900000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	691300000	usd
CY2023	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	11000000.0	usd
CY2023Q4	us-gaap	Goodwill Goodwill	702300000	usd
CY2023Q4	ntrs	Contractual Maturities Time Deposits250000 Or More Next Twelve Months ContractualMaturitiesTimeDeposits250000OrMoreNextTwelveMonths	5974100000	usd
CY2023Q4	ntrs	Contractual Maturities Time Deposits250000 Or More Year Two ContractualMaturitiesTimeDeposits250000OrMoreYearTwo	39300000	usd
CY2023Q4	ntrs	Contractual Maturities Time Deposits250000 Or More Year Three ContractualMaturitiesTimeDeposits250000OrMoreYearThree	6700000	usd
CY2023Q4	ntrs	Contractual Maturities Time Deposits250000 Or More Year Four ContractualMaturitiesTimeDeposits250000OrMoreYearFour	2100000	usd
CY2023Q4	ntrs	Contractual Maturities Time Deposits250000 Or More Year Five ContractualMaturitiesTimeDeposits250000OrMoreYearFive	9900000	usd
CY2023Q4	ntrs	Contractual Maturities Time Deposits250000 Or More After Year Five ContractualMaturitiesTimeDeposits250000OrMoreAfterYearFive	0	usd
CY2023Q4	ntrs	Time Deposits250000 Or More TimeDeposits250000OrMore	6032100000	usd
CY2022Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	3721800000	usd
CY2022Q4	us-gaap	Interest Bearing Domestic Deposit Certificates Of Deposits InterestBearingDomesticDepositCertificatesOfDeposits	1697600000	usd
CY2022Q4	us-gaap	Deposits Foreign DepositsForeign	2024200000	usd
CY2023Q4	us-gaap	Senior Notes SeniorNotes	2773200000	usd
CY2022Q4	us-gaap	Senior Notes SeniorNotes	2724200000	usd
CY2023Q4	us-gaap	Subordinated Debt SubordinatedDebt	2065000000	usd
CY2022Q4	us-gaap	Subordinated Debt SubordinatedDebt	2066200000	usd
CY2023Q4	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	2000000000	usd
CY2022Q4	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	0	usd
CY2023Q4	ntrs	Subordinated Debt And Long Term Federal Home Loan Bank Advances SubordinatedDebtAndLongTermFederalHomeLoanBankAdvances	4065000000	usd
CY2022Q4	ntrs	Subordinated Debt And Long Term Federal Home Loan Bank Advances SubordinatedDebtAndLongTermFederalHomeLoanBankAdvances	2066200000	usd
CY2023Q4	ntrs	Long Term Debt Qualifying As Risk Based Capital LongTermDebtQualifyingAsRiskBasedCapital	1490800000	usd
CY2022Q4	ntrs	Long Term Debt Qualifying As Risk Based Capital LongTermDebtQualifyingAsRiskBasedCapital	1648500000	usd
CY2023	us-gaap	Debt Instrument Redemption Price Percentage DebtInstrumentRedemptionPricePercentage	1
CY2023Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	10000000	shares
CY2021Q4	us-gaap	Stock Repurchase Program Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased	25000000	shares
CY2023	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	4384678	shares
CY2023	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	378130	shares
CY2023	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	347500000	usd
CY2022	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	311536	shares
CY2022	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	35400000	usd
CY2021	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	2527544	shares
CY2021	ntrs	Treasury Stock Share Based Compensation Shares Acquired TreasuryStockShareBasedCompensationSharesAcquired	394326	shares
CY2021	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	267600000	usd
CY2023	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	79.26
CY2022	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	113.70
CY2021	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	105.90
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	208428309	shares
CY2021Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	207761875	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	208289178	shares
CY2023	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	1040450	shares
CY2022	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	914404	shares
CY2021	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	1162484	shares
CY2023	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	42143	shares
CY2022	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	63566	shares
CY2021	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	837757	shares
CY2023	us-gaap	Stock Redeemed Or Called During Period Shares StockRedeemedOrCalledDuringPeriodShares	4384678	shares
CY2022	us-gaap	Stock Redeemed Or Called During Period Shares StockRedeemedOrCalledDuringPeriodShares	311536	shares
CY2021	us-gaap	Stock Redeemed Or Called During Period Shares StockRedeemedOrCalledDuringPeriodShares	2527544	shares
CY2023Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	205126224	shares
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	208428309	shares
CY2021Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	207761875	shares
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-463600000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1533600000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	431300000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	551500000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	120200000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	431300000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-2004900000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-471300000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1533600000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-590200000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-126600000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-463600000	usd
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	207248094	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	208309331	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	208075522	shares
CY2023	us-gaap	Net Income Loss NetIncomeLoss	1107300000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1336000000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	1545300000	usd
CY2023	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41800000	usd
CY2022	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41800000	usd
CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41800000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1065500000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1294200000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1503500000	usd
CY2023	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	11600000	usd
CY2022	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	11800000	usd
CY2021	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	12900000	usd
CY2023	ntrs	Net Income Loss Allocated To Common Stockholders Basic NetIncomeLossAllocatedToCommonStockholdersBasic	1053900000	usd
CY2022	ntrs	Net Income Loss Allocated To Common Stockholders Basic NetIncomeLossAllocatedToCommonStockholdersBasic	1282400000	usd
CY2021	ntrs	Net Income Loss Allocated To Common Stockholders Basic NetIncomeLossAllocatedToCommonStockholdersBasic	1490600000	usd
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.09
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.16
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	7.16
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	207248094	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	208309331	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	208075522	shares
CY2023	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	315652	shares
CY2022	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	557933	shares
CY2021	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	823708	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	207563746	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	208867264	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	208899230	shares
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	1053900000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	1282400000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	1490600000	usd
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.08
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.14
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	7.14
CY2023	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	100000	shares
CY2021	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2022	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2023	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4361800000	usd
CY2022	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4432600000	usd
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4361100000	usd
CY2023	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	203900000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	288600000	usd
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	292600000	usd
CY2023	ntrs	Treasury Management Fees TreasuryManagementFees	31600000	usd
CY2022	ntrs	Treasury Management Fees TreasuryManagementFees	39300000	usd
CY2021	ntrs	Treasury Management Fees TreasuryManagementFees	44300000	usd
CY2023	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	135000000.0	usd
CY2022	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	136200000	usd
CY2021	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	140200000	usd
CY2023	us-gaap	Other Operating Income OtherOperatingIncome	228700000	usd
CY2022	us-gaap	Other Operating Income OtherOperatingIncome	191300000	usd
CY2021	us-gaap	Other Operating Income OtherOperatingIncome	243900000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-169500000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-214000000.0	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-300000	usd
CY2023	ntrs	Other Noninterest Income OtherNoninterestIncome	429700000	usd
CY2022	ntrs	Other Noninterest Income OtherNoninterestIncome	441400000	usd
CY2021	ntrs	Other Noninterest Income OtherNoninterestIncome	720700000	usd
CY2023	us-gaap	Noninterest Income NoninterestIncome	4791500000	usd
CY2022	us-gaap	Noninterest Income NoninterestIncome	4874000000	usd
CY2021	us-gaap	Noninterest Income NoninterestIncome	5081800000	usd
CY2023	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	135000000	usd
CY2023	us-gaap	Other Operating Income OtherOperatingIncome	228700000	usd
CY2022	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	136200000	usd
CY2022	us-gaap	Other Operating Income OtherOperatingIncome	191300000	usd
CY2021	ntrs	Security Commissionsand Trading Income SecurityCommissionsandTradingIncome	140200000	usd
CY2021	us-gaap	Other Operating Income OtherOperatingIncome	243900000	usd
CY2023Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	928400000	usd
CY2022Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	937900000	usd
CY2023	ntrs	Interest Income Federal Reserve Deposits And Other InterestIncomeFederalReserveDepositsAndOther	1462300000	usd
CY2022	ntrs	Interest Income Federal Reserve Deposits And Other InterestIncomeFederalReserveDepositsAndOther	472000000.0	usd
CY2021	ntrs	Interest Income Federal Reserve Deposits And Other InterestIncomeFederalReserveDepositsAndOther	11300000	usd
CY2023	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	130100000	usd
CY2022	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	46600000	usd
CY2021	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	9100000	usd
CY2023	us-gaap	Interest Income Federal Funds Sold InterestIncomeFederalFundsSold	300000	usd
CY2022	us-gaap	Interest Income Federal Funds Sold InterestIncomeFederalFundsSold	100000	usd
CY2021	us-gaap	Interest Income Federal Funds Sold InterestIncomeFederalFundsSold	0	usd
CY2023	us-gaap	Interest Income Securities Purchased Under Agreements To Resell InterestIncomeSecuritiesPurchasedUnderAgreementsToResell	1585200000	usd
CY2022	us-gaap	Interest Income Securities Purchased Under Agreements To Resell InterestIncomeSecuritiesPurchasedUnderAgreementsToResell	103700000	usd
CY2021	us-gaap	Interest Income Securities Purchased Under Agreements To Resell InterestIncomeSecuritiesPurchasedUnderAgreementsToResell	3500000	usd
CY2023	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	1534400000	usd
CY2022	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	899900000	usd
CY2021	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	658800000	usd
CY2023	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	1300000	usd
CY2022	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	1300000	usd
CY2021	us-gaap	Interest Income Securities Tax Exempt InterestIncomeSecuritiesTaxExempt	1500000	usd
CY2023	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	2551100000	usd
CY2022	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	1344300000	usd
CY2021	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	713500000	usd
CY2023	us-gaap	Other Interest And Dividend Income OtherInterestAndDividendIncome	60300000	usd
CY2022	us-gaap	Other Interest And Dividend Income OtherInterestAndDividendIncome	9800000	usd
CY2021	us-gaap	Other Interest And Dividend Income OtherInterestAndDividendIncome	8800000	usd
CY2023	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	7325000000	usd
CY2022	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	2877700000	usd
CY2021	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	1406500000	usd
CY2023	us-gaap	Interest Expense Deposits InterestExpenseDeposits	2685300000	usd
CY2022	us-gaap	Interest Expense Deposits InterestExpenseDeposits	602800000	usd
CY2021	us-gaap	Interest Expense Deposits InterestExpenseDeposits	-61300000	usd
CY2023	us-gaap	Interest Expense Federal Funds Purchased InterestExpenseFederalFundsPurchased	256900000	usd
CY2022	us-gaap	Interest Expense Federal Funds Purchased InterestExpenseFederalFundsPurchased	34100000	usd
CY2021	us-gaap	Interest Expense Federal Funds Purchased InterestExpenseFederalFundsPurchased	-400000	usd
CY2023	us-gaap	Interest Expense Securities Sold Under Agreements To Repurchase InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase	1541100000	usd
CY2022	us-gaap	Interest Expense Securities Sold Under Agreements To Repurchase InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase	90700000	usd
CY2021	us-gaap	Interest Expense Securities Sold Under Agreements To Repurchase InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase	200000	usd
CY2023	us-gaap	Interest Expense Other Short Term Borrowings InterestExpenseOtherShortTermBorrowings	542500000	usd
CY2022	us-gaap	Interest Expense Other Short Term Borrowings InterestExpenseOtherShortTermBorrowings	126200000	usd
CY2021	us-gaap	Interest Expense Other Short Term Borrowings InterestExpenseOtherShortTermBorrowings	14200000	usd
CY2023	ntrs	Interest Expense Senior Notes InterestExpenseSeniorNotes	170000000.0	usd
CY2022	ntrs	Interest Expense Senior Notes InterestExpenseSeniorNotes	92700000	usd
CY2021	ntrs	Interest Expense Senior Notes InterestExpenseSeniorNotes	48300000	usd
CY2023	us-gaap	Interest Expense Other Long Term Debt InterestExpenseOtherLongTermDebt	147200000	usd
CY2022	us-gaap	Interest Expense Other Long Term Debt InterestExpenseOtherLongTermDebt	44000000.0	usd
CY2021	us-gaap	Interest Expense Other Long Term Debt InterestExpenseOtherLongTermDebt	21100000	usd
CY2023	us-gaap	Interest Expense Junior Subordinated Debentures InterestExpenseJuniorSubordinatedDebentures	0	usd
CY2022	us-gaap	Interest Expense Junior Subordinated Debentures InterestExpenseJuniorSubordinatedDebentures	0	usd
CY2021	us-gaap	Interest Expense Junior Subordinated Debentures InterestExpenseJuniorSubordinatedDebentures	1700000	usd
CY2023	us-gaap	Interest Expense InterestExpense	5343000000	usd
CY2022	us-gaap	Interest Expense InterestExpense	990500000	usd
CY2021	us-gaap	Interest Expense InterestExpense	23800000	usd
CY2023	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	1982000000	usd
CY2022	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	1887200000	usd
CY2021	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	1382700000	usd
CY2023	us-gaap	Other Operating Income OtherOperatingIncome	228700000	usd
CY2022	us-gaap	Other Operating Income OtherOperatingIncome	191300000	usd
CY2021	us-gaap	Other Operating Income OtherOperatingIncome	243900000	usd
CY2023	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	74800000	usd
CY2022	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	76700000	usd
CY2021	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	65500000	usd
CY2023	us-gaap	Other Labor Related Expenses OtherLaborRelatedExpenses	35000000.0	usd
CY2022	us-gaap	Other Labor Related Expenses OtherLaborRelatedExpenses	34600000	usd
CY2021	us-gaap	Other Labor Related Expenses OtherLaborRelatedExpenses	33900000	usd
CY2023	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	112000000.0	usd
CY2022	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	17800000	usd
CY2021	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	14600000	usd
CY2023	ntrs	Charitable Contributions Other CharitableContributionsOther	15600000	usd
CY2022	ntrs	Charitable Contributions Other CharitableContributionsOther	19400000	usd
CY2021	ntrs	Charitable Contributions Other CharitableContributionsOther	18000000.0	usd
CY2023	ntrs	Noninterest Expense Other NoninterestExpenseOther	235500000	usd
CY2022	ntrs	Noninterest Expense Other NoninterestExpenseOther	210800000	usd
CY2021	ntrs	Noninterest Expense Other NoninterestExpenseOther	167100000	usd
CY2023	us-gaap	Other Noninterest Expense OtherNoninterestExpense	472900000	usd
CY2022	us-gaap	Other Noninterest Expense OtherNoninterestExpense	359300000	usd
CY2021	us-gaap	Other Noninterest Expense OtherNoninterestExpense	299100000	usd
CY2023Q4	ntrs	Federal Deposit Insurance Corporation Premium Expense Special Assessment FederalDepositInsuranceCorporationPremiumExpenseSpecialAssessment	84600000	usd
CY2023Q4	ntrs	Federal Deposit Insurance Corporation Premium Expense Special Assessment FederalDepositInsuranceCorporationPremiumExpenseSpecialAssessment	84600000	usd
CY2023	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2022	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2021	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2023	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.034
CY2022	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.033
CY2021	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.034
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.006
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.001
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.001
CY2023	ntrs	Income Tax Reconciliation Leveraged Lease Adjustments IncomeTaxReconciliationLeveragedLeaseAdjustments	-0.001
CY2022	ntrs	Income Tax Reconciliation Leveraged Lease Adjustments IncomeTaxReconciliationLeveragedLeaseAdjustments	-0.002
CY2021	ntrs	Income Tax Reconciliation Leveraged Lease Adjustments IncomeTaxReconciliationLeveragedLeaseAdjustments	-0.004
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.027
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.020
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.016
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.014
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.009
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.006
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.018
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.015
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.006
CY2023	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.018
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.016
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.006
CY2023	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.244
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.244
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.231
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	357500000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	430300000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	464800000	usd
CY2023	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.244
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.244
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.231
CY2021	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	26800000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	60700000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	40700000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	54400000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	37400000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	40700000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	25300000	usd
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	22400000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	2100000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1700000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1200000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	24000000.0	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	13700000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	4200000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	5100000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	usd
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	2500000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	1000000.0	usd
CY2022	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	usd
CY2021	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	0	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	60700000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	40700000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	25300000	usd
CY2023	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	200000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-126600000	usd
CY2022	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	11100000	usd
CY2021	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	-400000	usd
CY2023Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	22700000	usd
CY2022Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	22200000	usd
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	250500000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	357700000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	241500000	usd
CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	63200000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	84700000	usd
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	74000000.0	usd
CY2023	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	92000000.0	usd
CY2022	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	130600000	usd
CY2021	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	147300000	usd
CY2023	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	405700000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	573000000.0	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	462800000	usd
CY2023	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-54000000.0	usd
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-126000000.0	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-11700000	usd
CY2023	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-1400000	usd
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-10700000	usd
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	12000000.0	usd
CY2023	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	7200000	usd
CY2022	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-6000000.0	usd
CY2021	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	1700000	usd
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-48200000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-142700000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	2000000.0	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	357500000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	430300000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	464800000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	120200000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-471300000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Software DeferredTaxLiabilitiesDeferredExpenseCapitalizedSoftware	394900000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Software DeferredTaxLiabilitiesDeferredExpenseCapitalizedSoftware	354700000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	23900000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	122600000	usd
CY2023Q4	ntrs	Deferred Tax Liabilities Compensation And Benefits DeferredTaxLiabilitiesCompensationAndBenefits	0	usd
CY2022Q4	ntrs	Deferred Tax Liabilities Compensation And Benefits DeferredTaxLiabilitiesCompensationAndBenefits	5200000	usd
CY2023Q4	ntrs	Deferred Tax Liabilities State Taxes DeferredTaxLiabilitiesStateTaxes	46800000	usd
CY2022Q4	ntrs	Deferred Tax Liabilities State Taxes DeferredTaxLiabilitiesStateTaxes	58300000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	53400000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	42100000	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	519000000.0	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	582900000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	46200000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	41800000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	244600000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	427300000	usd
CY2023Q4	ntrs	Deferred Tax Assets Compensation And Benefits DeferredTaxAssetsCompensationAndBenefits	70200000	usd
CY2022Q4	ntrs	Deferred Tax Assets Compensation And Benefits DeferredTaxAssetsCompensationAndBenefits	0	usd
CY2023Q4	ntrs	Deferred Tax Assets Tax Credit Carryforwards And Operating Loss Carryforwards DeferredTaxAssetsTaxCreditCarryforwardsAndOperatingLossCarryforwards	121200000	usd
CY2022Q4	ntrs	Deferred Tax Assets Tax Credit Carryforwards And Operating Loss Carryforwards DeferredTaxAssetsTaxCreditCarryforwardsAndOperatingLossCarryforwards	95300000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	116000000.0	usd
CY2022Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	143700000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	598200000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	708100000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	121200000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	95300000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	477000000.0	usd
CY2022Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	612800000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	42000000.0	usd
CY2022Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	29900000	usd
CY2023	us-gaap	Defined Benefit Plan Actuarial Gain Loss DefinedBenefitPlanActuarialGainLoss	-53300000	usd
CY2022	us-gaap	Defined Benefit Plan Actuarial Gain Loss DefinedBenefitPlanActuarialGainLoss	365500000	usd
CY2023	ntrs	Number Of Investments Held In Diversified Portfolios NumberOfInvestmentsHeldInDiversifiedPortfolios	1	investment
CY2023Q4	us-gaap	Derivative Number Of Instruments Held DerivativeNumberOfInstrumentsHeld	4	numberofderivativeinstruments
CY2022Q4	us-gaap	Derivative Number Of Instruments Held DerivativeNumberOfInstrumentsHeld	4	numberofderivativeinstruments
CY2023	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Expected Long Term Return On Assets DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets	0.0725
CY2023	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	72400000	usd
CY2022	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	67200000	usd
CY2021	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	65300000	usd
CY2023	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	118200000	usd
CY2022	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	125200000	usd
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	95500000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	29900000	usd
CY2022	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	31400000	usd
CY2021	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	24000000.0	usd
CY2023Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	96000000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P3Y
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	0	usd
CY2022	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	0	usd
CY2021	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	2200000	usd
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	1600000	usd
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	3600000	usd
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	41300000	usd
CY2023	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	2300000	usd
CY2022	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	3900000	usd
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	53800000	usd
CY2023	ntrs	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Option EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOption	1600000	usd
CY2022	ntrs	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Option EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOption	3500000	usd
CY2021	ntrs	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Option EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOption	41300000	usd
CY2023Q4	us-gaap	Deferred Compensation Arrangement With Individual Cash Award Granted Amount DeferredCompensationArrangementWithIndividualCashAwardGrantedAmount	358700000	usd
CY2022Q4	us-gaap	Deferred Compensation Arrangement With Individual Cash Award Granted Amount DeferredCompensationArrangementWithIndividualCashAwardGrantedAmount	392700000	usd
CY2021Q4	us-gaap	Deferred Compensation Arrangement With Individual Cash Award Granted Amount DeferredCompensationArrangementWithIndividualCashAwardGrantedAmount	377100000	usd
CY2023	us-gaap	Loss Contingency Disclosures LossContingencyDisclosures	Commitments and Contingent Liabilities<div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Off-Balance Sheet Financial Instruments, Guarantees and Other Commitments. </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Northern Trust, in the normal course of business, enters into various types of commitments and issues letters of credit to meet the liquidity and credit enhancement needs of its clients. The contractual amounts of these instruments represent the maximum potential credit exposure should the instrument be fully drawn upon and the client default. To control the credit risk associated with entering into commitments and issuing letters of credit, Northern Trust subjects such activities to the same credit quality and monitoring controls as its lending activities. Northern Trust does not believe the total contractual amount of these instruments to be representative of its future credit exposure or funding requirements. </span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The following table provides details of Northern Trust's off-balance sheet financial instruments as of December 31, 2023 and 2022.</span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:120%">TABLE 115: SUMMARY OF OFF-BALANCE SHEET FINANCIAL INSTRUMENTS</span></div><div style="margin-top:5pt"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:40.718%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:8.596%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:8.596%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:8.596%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:8.596%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:8.596%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:8.602%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="18" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">DECEMBER 31,</span></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="9" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">2023</span></td><td colspan="9" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">2022</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">(In Millions)</span></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">ONE YEAR AND LESS</span></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">OVER ONE YEAR</span></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">TOTAL</span></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">ONE YEAR AND LESS</span></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">OVER ONE YEAR</span></td><td colspan="3" style="border-top:1pt solid #000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">TOTAL</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Undrawn Commitments</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(1)</span></div></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">11,849.5</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">18,909.6</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">30,759.1</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">13,639.2 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">17,321.4 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">30,960.6 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Standby Letters of Credit and Financial Guarantees</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(2)(3)</span></div></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">85,752.0</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">639.0</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">86,391.0</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">17,553.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">409.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">17,962.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Commercial Letters of Credit</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">29.2</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">1.3</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">30.5</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">25.4 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">1.3 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">26.7 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Securities Lent with Indemnification</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">140,539.1</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">140,539.1</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">130,311.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">130,311.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Unsettled Reverse Repurchase Agreements</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">27,667.7</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">27,667.7</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">496.8 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">496.8 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total Off-Balance Sheet Financial Instruments</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">265,837.5</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">19,549.9</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">285,387.4</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">162,025.4 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">17,732.6 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">179,758.0 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr></table></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:4.55pt;font-style:italic;font-weight:400;line-height:120%;position:relative;top:-2.44pt;vertical-align:baseline">(1)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-style:italic;font-weight:400;line-height:120%"> These amounts exclude $222.2 million and $266.6 million of commitments participated to others at December 31, 2023 and 2022, respectively.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:4.55pt;font-style:italic;font-weight:400;line-height:120%;position:relative;top:-2.44pt;vertical-align:baseline">(2) </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-style:italic;font-weight:400;line-height:120%">These amounts include $39.1 million and $35.1 million of standby letters of credit secured by cash deposits or participated to others as of December 31, 2023 and 2022, respectively.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:4.55pt;font-style:italic;font-weight:400;line-height:120%;position:relative;top:-2.44pt;vertical-align:baseline">(3) </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-style:italic;font-weight:400;line-height:120%">This amount includes a $84.6 billion guarantee to the Fixed Income Clearing Corporation (FICC) under the sponsored member program, without taking into consideration the related collateral, as of December 31, 2023. As of December 31, 2022, there was a $16.3 billion guarantee to the FICC; Northern Trust became a sponsored member during the third quarter of 2021. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Undrawn Commitments</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> generally have fixed expiration dates or other termination clauses. Since a significant portion of the commitments are expected to expire without being drawn upon, the total commitment amount does not necessarily represent future loans or liquidity requirements.</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Standby Letters of Credit</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> obligate Northern Trust to meet certain financial obligations of its clients, if, under the contractual terms of the agreement, the clients are unable to do so. These instruments are primarily issued to support public and private financial commitments, including commercial paper, bond financing, initial margin requirements on futures exchanges, and similar transactions. Northern Trust is obligated to meet the entire financial obligation of these agreements and in certain cases is able to recover the amounts paid through recourse against collateral received or other participants. Since the vast majority of the standby letters of credit are never drawn, the total standby letters of credit amount does not necessarily represent future loans or liquidity requirements.</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Financial Guarantees</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> are issued by Northern Trust to guarantee the performance of a client to a third party under certain arrangements.</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Commercial Letters of Credit</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> are instruments issued by Northern Trust on behalf of its clients that authorize a third party (the beneficiary) to draw drafts up to a stipulated amount under the specified terms and conditions of the agreement and other similar instruments. Commercial letters of credit are issued primarily to facilitate international trade.</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Securities Lent with Indemnification</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> involves Northern Trust lending securities owned by clients to borrowers who are reviewed and approved by the Northern Trust Capital Markets Credit Committee, as part of its securities custody activities and at the direction of its clients. In connection with these activities, Northern Trust has issued indemnifications to certain clients against certain losses that are a direct result of a borrower’s failure to return securities when due, should the value of such securities exceed the value of the collateral required to be posted. Borrowers are required to fully collateralize securities received with cash or marketable securities. As securities are loaned, collateral is maintained at a minimum of 100% of the fair value of the securities plus accrued interest. The collateral is revalued on a daily basis. The amount of securities loaned subject to indemnification as of December 31, 2023 and December 31, 2022, was $140.5 billion and $130.3 billion, respectively. Because of the credit quality of the borrowers and the requirement to fully collateralize securities borrowed, management believes that the exposure to credit loss from this activity is not significant and no liability was recorded at December 31, 2023, or 2022 related to these indemnifications.</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Unsettled Repurchase and Reverse Repurchase Agreements</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">.</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> Northern Trust enters into repurchase agreements and reverse repurchase agreements which may settle at a future date. In repurchase agreements, Northern Trust receives cash from and provides securities as collateral to a counterparty. In reverse repurchase agreements, Northern Trust advances cash to and receives securities as collateral from a counterparty. These transactions are recorded on the consolidated balance sheets on the settlement date. As of December 31, 2023, and 2022, there were $27.7 billion and $496.8 million of unsettled reverse repurchase agreements, and no unsettled repurchase agreements, respectively.</span></div><div style="text-align:justify;text-indent:18pt"><span><br/></span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Sponsored Member Program. </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Northern Trust is an approved Government Securities Division (GSD) netting and sponsoring member in the Fixed Income Clearing Corporation (FICC) sponsored member program, through which Northern Trust submits eligible repurchase and reverse repurchase transactions in U.S. government securities between Northern Trust and its sponsored member clients for novation and clearing. Northern Trust may sponsor clients to clear </span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">their eligible repurchase transactions with the FICC. As a sponsoring member, Northern Trust guarantees to the FICC the prompt and full payment and performance of its sponsored member clients’ respective obligations under the FICC GSD’s rules. To mitigate Northern Trust’s credit exposure under this guarantee, Northern Trust obtains a security interest in its sponsored member clients’ collateral. Please refer to Note 27, “Offsetting of Assets and Liabilities” for additional information on Northern Trust’s repurchase and reverse repurchase agreements.</span></div><div style="text-align:justify;text-indent:18pt"><span><br/></span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Clearing and Settlement Organizations.</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> The Bank is a participating member of various cash, securities and foreign exchange clearing and settlement organizations. It participates in these organizations on behalf of its clients and on its own behalf as a result of its own activities. A wide variety of cash and securities transactions are settled through these organizations, including those involving U.S. Treasuries, obligations of states and political subdivisions, asset-backed securities, commercial paper, dollar placements, and securities issued by the Government National Mortgage Association. </span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Certain of these industry clearing and settlement exchanges require their members to guarantee their obligations and liabilities and/or to provide liquidity support in the event other members do not honor their obligations as stipulated in each clearing organization’s membership agreement. Exposure related to these agreements varies, primarily as a result of fluctuations in the volume of transactions cleared through the organizations. At December 31, 2023 and 2022, Northern Trust has not recorded any material liabilities under these arrangements as Northern Trust believes the likelihood that a clearing or settlement exchange (of which Northern Trust is a member) would become insolvent is remote. Controls related to these clearing transactions are closely monitored by management to protect the assets of Northern Trust and its clients.</span></div><div style="text-indent:18pt"><span><br/></span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Legal Proceedings.</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> In the normal course of business, the Corporation and its subsidiaries are routinely defendants in or parties to pending and threatened legal actions, and are subject to regulatory examinations, information-gathering requests, investigations, and proceedings, both formal and informal. In certain legal actions, claims for substantial monetary damages are asserted. In regulatory matters, claims for disgorgement, restitution, penalties and/or other remedial actions or sanctions may be sought. </span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Based on current knowledge, after consultation with legal counsel and after taking into account current accruals, management does not believe that losses, fines or penalties, if any, arising from pending litigation or threatened legal actions or regulatory matters either individually or in the aggregate, after giving effect to applicable reserves and insurance coverage will have a material adverse effect on the consolidated financial position or liquidity of the Corporation, although such matters could have a material adverse effect on the Corporation’s operating results for a particular period.</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Under GAAP, (i) an event is “probable” if the “future event or events are likely to occur”; (ii) an event is “reasonably possible” if “the chance of the future event or events occurring is more than remote but less than likely”; and (iii) an event is “remote” if “the chance of the future event or events occurring is slight.”</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The outcome of litigation and regulatory matters is inherently difficult to predict and/or the range of loss often cannot be reasonably estimated, particularly for matters that (i) will be decided by a jury, (ii) are in early stages, (iii) involve uncertainty as to the likelihood of a class being certified or the ultimate size of the class, (iv) are subject to appeals or motions, (v) involve significant factual issues to be resolved, including with respect to the amount of damages, (vi) do not specify the amount of damages sought or (vii) seek very large damages based on novel and complex damage and liability legal theories. Accordingly, the Corporation cannot reasonably estimate the eventual outcome of these pending matters, the timing of their ultimate resolution or what the eventual loss, fines or penalties, if any, related to each pending matter will be.</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In accordance with applicable accounting guidance, the Corporation records accruals for litigation and regulatory matters when those matters present loss contingencies that are both probable and reasonably estimable. When loss contingencies are not both probable and reasonably estimable, the Corporation does not record accruals. No material accruals have been recorded for pending litigation or threatened legal actions or regulatory matters. </span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">For a limited number of matters for which a loss is reasonably possible in future periods, whether in excess of an accrued liability or where there is no accrued liability, the Corporation is able to estimate a range of possible loss. As of December 31, 2023, the Corporation has estimated the range of reasonably possible loss for these matters to be from zero to approximately $25 million in the aggregate. The Corporation’s estimate with respect to the aggregate range of reasonably possible loss is based upon currently available information and is subject to significant judgment and a variety of assumptions and known and unknown uncertainties. The matters underlying the estimated range will change from time to time, and actual results may vary significantly from the current estimate. </span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In certain other pending matters, there may be a range of reasonably possible loss (including reasonably possible loss in excess of amounts accrued) that cannot be reasonably estimated for the reasons described above. Such matters are not included in the estimated range of reasonably possible loss discussed above. </span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In 2015, Northern Trust Fiduciary Services (Guernsey) Limited (NTFS), an indirect subsidiary of the Corporation, was charged by a French investigating magistrate judge with complicity in estate tax fraud in connection with the administration of two trusts for which it serves as trustee. Charges also were brought against a number of other persons and </span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">entities related to this matter. In 2017, a French court found no estate tax fraud had occurred and NTFS and all other persons and entities charged were acquitted. The Public Prosecutor’s Office of France appealed the court decision and in June 2018 a French appellate court issued its opinion on the matter, acquitting all persons and entities charged, including NTFS. In January 2021, the Cour de Cassation, the highest court in France, reversed the June 2018 appellate court ruling, requiring a re-trial at the appellate court level. This re-trial concluded in October 2023 and the appellate court is expected to render its verdict in March 2024. As trustee, NTFS provided no tax advice and had no involvement in the preparation or filing of the challenged estate tax filings.</span></div><div style="text-align:justify;text-indent:18pt"><span><br/></span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Visa Class B Common Shares.</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> Northern Trust, as a member of Visa U.S.A. Inc. (Visa U.S.A.) and in connection with the 2007 restructuring of Visa U.S.A. and its affiliates and the 2008 initial public offering of Visa Inc. (Visa), received certain Visa Class B common shares. The Visa Class B common shares are subject to certain transfer restrictions until the final resolution of certain litigation related to interchange fees involving Visa (the covered litigation), at which time the shares are convertible into Visa Class A common shares based on a conversion rate dependent upon the ultimate cost of resolving the covered litigation. Since 2018, Visa has deposited an additional $2.8 billion into an escrow account previously established with respect to the covered litigation. As a result of the additional contributions to the escrow account, the rate at which Visa Class B common shares will convert into Visa Class A common shares was reduced to 1.5875 as of December 31, 2023. </span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In September 2018, Visa reached a proposed class settlement agreement covering damage claims but not injunctive relief claims regarding the covered litigation. In December 2019, the district court granted final approval for the proposed class settlement agreement. In March 2023, the Second Circuit Court of Appeals affirmed the district court’s approval of the class settlement agreement. Certain merchants have opted out of the class settlement and are pursuing claims separately. The ultimate resolution of the covered litigation, the timing for removal of the selling restrictions on the Visa Class B common shares and the rate at which such shares will ultimately convert into Visa Class A common shares are uncertain.</span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On January 29, 2024, Visa filed a registration statement under the Securities Act of 1933 with the SEC. This registration statement has not yet become effective. If Visa commences the exchange offer contemplated by the registration statement, Visa Class B shareholders would have the option to tender some or all of their Class B shares and in return receive shares of a newly issued series of Visa Class B common shares with a value equal to half the value of the tendered shares and Visa Class C common shares with value equal to the other half of the tendered shares. The newly issued series of Visa Class B common shares would be subject to the same transfer and convertibility restrictions as the currently outstanding Visa Class B common shares. One third of the Visa Class C common shares received would be transferable within the first 45 days following the potential exchange, up to two-thirds would be transferable within the first 90 days, and all such shares would be transferable after 90 days. The Visa Class C common shares will automatically be converted at the then applicable conversion rate into shares of Visa Class A common stock if transferred to a person other than a Visa member or an affiliate of a Visa member. After the initial exchange offer, Visa could, at its discretion, conduct up to three successive potential exchange offers, in each case, if more than 12 months have passed since the previous exchange offer and after a further 50% reduction of interchange fees at issue in the unresolved claims for damages in the covered litigation. </span></div><div style="text-align:justify;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In June 2016 and 2015, Northern Trust recorded a $123.1 million and $99.9 million net gain on the sale of 1.1 million and 1.0 million of its Visa Class B common shares, respectively. These sales do not affect Northern Trust’s risk related to the impact of the covered litigation on the rate at which such shares will ultimately convert into Visa Class A common shares. Northern Trust continued to hold approximately 4.1 million Visa Class B common shares, which are recorded at their original cost basis of zero, as of both December 31, 2023 and 2022.</span></div>
CY2023Q4	ntrs	Fair Value Disclosure Off Balance Sheet Risks Amount Current Liability FairValueDisclosureOffBalanceSheetRisksAmountCurrentLiability	265837500000	usd
CY2023Q4	ntrs	Fair Value Disclosure Off Balance Sheet Risks Amount Non Current Liability FairValueDisclosureOffBalanceSheetRisksAmountNonCurrentLiability	19549900000	usd
CY2023Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	285387400000	usd
CY2022Q4	ntrs	Fair Value Disclosure Off Balance Sheet Risks Amount Current Liability FairValueDisclosureOffBalanceSheetRisksAmountCurrentLiability	162025400000	usd
CY2022Q4	ntrs	Fair Value Disclosure Off Balance Sheet Risks Amount Non Current Liability FairValueDisclosureOffBalanceSheetRisksAmountNonCurrentLiability	17732600000	usd
CY2022Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	179758000000	usd
CY2023Q4	ntrs	Securities Lending Related Collateral Maintenance SecuritiesLendingRelatedCollateralMaintenance	1
CY2023Q4	us-gaap	Resell Agreements Period End Amounts Excluding Effects Of Agreements Reported Net By Counterparty ResellAgreementsPeriodEndAmountsExcludingEffectsOfAgreementsReportedNetByCounterparty	27700000000	usd
CY2022Q4	us-gaap	Resell Agreements Period End Amounts Excluding Effects Of Agreements Reported Net By Counterparty ResellAgreementsPeriodEndAmountsExcludingEffectsOfAgreementsReportedNetByCounterparty	496800000	usd
CY2022Q4	us-gaap	Repurchase Agreement Counterparty Amount At Risk RepurchaseAgreementCounterpartyAmountAtRisk	0	usd
CY2023Q4	us-gaap	Repurchase Agreement Counterparty Amount At Risk RepurchaseAgreementCounterpartyAmountAtRisk	0	usd
CY2023Q4	us-gaap	Loss Contingency Accrual At Carrying Value LossContingencyAccrualAtCarryingValue	0	usd
CY2023	ntrs	Paymentto Escrow Deposit PaymenttoEscrowDeposit	2800000000	usd
CY2023Q4	ntrs	Common Stock Convertible Conversion Price CommonStockConvertibleConversionPrice	1.5875
CY2023Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	340383300000	usd
CY2023Q4	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	3568200000	usd
CY2023Q4	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	3649800000	usd
CY2022Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	310684300000	usd
CY2022Q4	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	3732400000	usd
CY2022Q4	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	3654100000	usd
CY2023Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	3126700000	usd
CY2023Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	2205400000	usd
CY2022Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	2810700000	usd
CY2022Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	1865900000	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	441500000	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	1444400000	usd
CY2022Q4	us-gaap	Derivative Assets DerivativeAssets	921700000	usd
CY2022Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	1788200000	usd
CY2023	us-gaap	Gain Loss On Discontinuation Of Cash Flow Hedge Due To Forecasted Transaction Probable Of Not Occurring Net GainLossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurringNet	0	usd
CY2022	us-gaap	Gain Loss On Discontinuation Of Cash Flow Hedge Due To Forecasted Transaction Probable Of Not Occurring Net GainLossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurringNet	0	usd
CY2021	us-gaap	Gain Loss On Discontinuation Of Cash Flow Hedge Due To Forecasted Transaction Probable Of Not Occurring Net GainLossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurringNet	0	usd
CY2023	us-gaap	Maximum Length Of Time Foreign Currency Cash Flow Hedge MaximumLengthOfTimeForeignCurrencyCashFlowHedge	P4M
CY2023	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	7325000000	usd
CY2022	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	2877700000	usd
CY2021	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	1406500000	usd
CY2023	us-gaap	Interest Expense InterestExpense	5343000000	usd
CY2022	us-gaap	Interest Expense InterestExpense	990500000	usd
CY2021	us-gaap	Interest Expense InterestExpense	23800000	usd
CY2023	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	228700000	usd
CY2022	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	191300000	usd
CY2021	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	243900000	usd
CY2023Q4	us-gaap	Hedged Asset Fair Value Hedge HedgedAssetFairValueHedge	5048800000	usd
CY2023Q4	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	77500000	usd
CY2022Q4	us-gaap	Hedged Asset Fair Value Hedge HedgedAssetFairValueHedge	1820800000	usd
CY2022Q4	us-gaap	Hedged Asset Fair Value Hedge Cumulative Increase Decrease HedgedAssetFairValueHedgeCumulativeIncreaseDecrease	-60200000	usd
CY2023Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	784700000	usd
CY2022Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	567200000	usd
CY2023Q4	us-gaap	Hedged Liability Fair Value Hedge HedgedLiabilityFairValueHedge	2495900000	usd
CY2023Q4	us-gaap	Hedged Liability Fair Value Hedge Cumulative Increase Decrease HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease	-248700000	usd
CY2022Q4	us-gaap	Hedged Liability Fair Value Hedge HedgedLiabilityFairValueHedge	2746200000	usd
CY2022Q4	us-gaap	Hedged Liability Fair Value Hedge Cumulative Increase Decrease HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease	-294000000.0	usd
CY2023Q4	ntrs	Hedged Asset Fair Value Hedge Discontinued Cumulative Increase Decrease HedgedAssetFairValueHedgeDiscontinuedCumulativeIncreaseDecrease	2200000	usd
CY2023Q4	ntrs	Hedged Liability Fair Value Hedge Discontinued Cumulative Increase Decrease HedgedLiabilityFairValueHedgeDiscontinuedCumulativeIncreaseDecrease	29600000	usd
CY2022Q4	ntrs	Hedged Asset Liability Fair Value Hedge Discontinued Cumulative Increase Decrease Net HedgedAssetLiabilityFairValueHedgeDiscontinuedCumulativeIncreaseDecreaseNet	7300000	usd
CY2022Q4	ntrs	Hedged Liability Fair Value Hedge Discontinued Cumulative Increase Decrease HedgedLiabilityFairValueHedgeDiscontinuedCumulativeIncreaseDecrease	0	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-77400000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	278700000	usd
CY2023	us-gaap	Schedule Of Resale Agreements ScheduleOfResaleAgreements	<div><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:78.627%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:9.036%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:9.037%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">($ In Millions)</span></td><td colspan="3" style="padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">2023</span></td><td colspan="3" style="padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">2022</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Balance at December 31</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">784.7</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">1,070.3 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Average Balance During the Year</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">950.9</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">1,071.2 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Average Interest Rate Earned During the Year</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">166.71</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">%</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">9.68 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">%</span></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Maximum Month-End Balance During the Year</span></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">1,326.2</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">1,320.8 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr></table></div>Note: The table above includes the impact of balance sheet netting of approximately $29.1 billion and $3.6 billion in 2023 and 2022, respectively.
CY2023Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	784700000	usd
CY2022Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	1070300000	usd
CY2023	ntrs	Securities Purchased Under Agreement To Resell Average Balance During Period SecuritiesPurchasedUnderAgreementToResellAverageBalanceDuringPeriod	950900000	usd
CY2022	ntrs	Securities Purchased Under Agreement To Resell Average Balance During Period SecuritiesPurchasedUnderAgreementToResellAverageBalanceDuringPeriod	1071200000	usd
CY2023	ntrs	Securities Purchased Under Agreement To Resell Average Interest Rate Earned During Period SecuritiesPurchasedUnderAgreementToResellAverageInterestRateEarnedDuringPeriod	1.6671
CY2022	ntrs	Securities Purchased Under Agreement To Resell Average Interest Rate Earned During Period SecuritiesPurchasedUnderAgreementToResellAverageInterestRateEarnedDuringPeriod	0.0968
CY2023	ntrs	Securities Purchased Under Agreement To Resell Maximum Month End Balance During Period SecuritiesPurchasedUnderAgreementToResellMaximumMonthEndBalanceDuringPeriod	1326200000	usd
CY2022	ntrs	Securities Purchased Under Agreement To Resell Maximum Month End Balance During Period SecuritiesPurchasedUnderAgreementToResellMaximumMonthEndBalanceDuringPeriod	1320800000	usd
CY2023Q4	ntrs	Securities Purchased Under Agreements To Resell Netting Impact SecuritiesPurchasedUnderAgreementsToResellNettingImpact	29100000000	usd
CY2022Q4	ntrs	Securities Purchased Under Agreements To Resell Netting Impact SecuritiesPurchasedUnderAgreementsToResellNettingImpact	3600000000	usd
CY2023	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<div style="margin-top:5pt"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"></td><td style="width:78.627%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:9.036%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:9.037%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">($ In Millions)</span></td><td colspan="3" style="padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:700;line-height:100%">2023</span></td><td colspan="3" style="padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7pt;font-weight:400;line-height:100%">2022</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Balance at December 31</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">784.7</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">567.2 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Average Balance During the Year</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">401.5</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">433.6 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Average Interest Rate Paid During the Year</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">383.84</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">%</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">20.94 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">%</span></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Maximum Month-End Balance During the Year</span></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">988.1</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">869.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr></table></div>Note: The table above includes the impact of balance sheet netting of approximately $29.1 billion and $3.6 billion in 2023 and 2022, respectively.
CY2023Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	784700000	usd
CY2022Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	567200000	usd
CY2023	ntrs	Securities Sold Under Agreements To Repurchase Average Balance During Period SecuritiesSoldUnderAgreementsToRepurchaseAverageBalanceDuringPeriod	401500000	usd
CY2022	ntrs	Securities Sold Under Agreements To Repurchase Average Balance During Period SecuritiesSoldUnderAgreementsToRepurchaseAverageBalanceDuringPeriod	433600000	usd
CY2023	ntrs	Securities Sold Under Agreements To Repurchase Average Interest Rate Paid During Period SecuritiesSoldUnderAgreementsToRepurchaseAverageInterestRatePaidDuringPeriod	3.8384
CY2022	ntrs	Securities Sold Under Agreements To Repurchase Average Interest Rate Paid During Period SecuritiesSoldUnderAgreementsToRepurchaseAverageInterestRatePaidDuringPeriod	0.2094
CY2023	ntrs	Securities Sold Under Agreements To Repurchase Maximum Month End Balance During Period SecuritiesSoldUnderAgreementsToRepurchaseMaximumMonthEndBalanceDuringPeriod	988100000	usd
CY2022	ntrs	Securities Sold Under Agreements To Repurchase Maximum Month End Balance During Period SecuritiesSoldUnderAgreementsToRepurchaseMaximumMonthEndBalanceDuringPeriod	869000000.0	usd
CY2023Q4	ntrs	Securities Sold Under Agreements To Repurchase Netting Impact SecuritiesSoldUnderAgreementsToRepurchaseNettingImpact	29100000000	usd
CY2022Q4	ntrs	Securities Sold Under Agreements To Repurchase Netting Impact SecuritiesSoldUnderAgreementsToRepurchaseNettingImpact	3600000000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	3307800000	usd
CY2023Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	3126700000	usd
CY2023Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	181100000	usd
CY2023Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	12200000	usd
CY2023Q4	us-gaap	Derivative Asset Fair Value After Offset And Deduction Subject To Master Netting Arrangement DerivativeAssetFairValueAfterOffsetAndDeductionSubjectToMasterNettingArrangement	168900000	usd
CY2023Q4	us-gaap	Derivative Asset Not Subject To Master Netting Arrangement DerivativeAssetNotSubjectToMasterNettingArrangement	260400000	usd
CY2023Q4	us-gaap	Derivative Asset Not Subject To Master Netting Arrangement DerivativeAssetNotSubjectToMasterNettingArrangement	260400000	usd
CY2023Q4	us-gaap	Derivative Asset Not Subject To Master Netting Arrangement DerivativeAssetNotSubjectToMasterNettingArrangement	260400000	usd
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CY2023	us-gaap	Net Income Loss NetIncomeLoss	1107300000	usd
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CY2023	us-gaap	Net Income Loss NetIncomeLoss	1107300000	usd
CY2022Q4	us-gaap	Assets Assets	155036700000	usd
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CY2022	us-gaap	Net Income Loss NetIncomeLoss	1336000000	usd
CY2021Q4	us-gaap	Assets Assets	183889800000	usd
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CY2021	us-gaap	Net Income Loss NetIncomeLoss	1545300000	usd
CY2023Q4	ecd	Non Rule10b51 Arr Adopted Flag NonRule10b51ArrAdoptedFlag	false
CY2023Q4	ecd	Rule10b51 Arr Adopted Flag Rule10b51ArrAdoptedFlag	false
CY2023Q4	ecd	Non Rule10b51 Arr Trmntd Flag NonRule10b51ArrTrmntdFlag	false
CY2023Q4	ecd	Rule10b51 Arr Trmntd Flag Rule10b51ArrTrmntdFlag	false
CY2023	dei	Auditor Name AuditorName	KPMG LLP
CY2023	dei	Auditor Location AuditorLocation	Chicago, IL
CY2023	dei	Auditor Firm AuditorFirmId	185

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$NTRS
NORTHERN TRUST CORP Stock $ntrs

2024 Q1 Form 10-K Financial Statement

#000007312424000073 Filed on February 27, 2024

Income Statement

Balance Sheet

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$NTRS NORTHERN TRUST CORP Stock $ntrs

2024 Q1 Form 10-K Financial Statement

#000007312424000073 Filed on February 27, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NTRS
NORTHERN TRUST CORP Stock $ntrs