$STT
STATE STREET CORP Stock $stt

$stt Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000009375121000476 Filed on February 19, 2021

Income Statement

Concept	2019 Q4	2018 Q4	2018
Revenue			$12.13B
YoY Change			7.68%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development			$1.324B
YoY Change			13.45%
% of Gross Profit
Depreciation & Amortization	$363.0M	$329.0M	$599.0M
YoY Change	10.33%	13.84%	13.88%
% of Gross Profit
Operating Expenses			$1.324B
YoY Change			13.45%
Operating Profit
YoY Change
Interest Expense			$991.0M
YoY Change			64.07%
% of Operating Profit
Other Income/Expense, Net			$1.176B
YoY Change			26.59%
Pretax Income	$638.0M	$529.0M	$3.101B
YoY Change	20.6%	-34.93%	3.54%
Income Tax	$74.00M	$124.0M	$508.0M
% Of Pretax Income	11.6%	23.44%	16.38%
Net Earnings	$564.0M	$437.0M	$2.593B
YoY Change	29.06%	25.21%	20.27%
Net Earnings / Revenue			21.37%
Basic Earnings Per Share			$6.46
Diluted Earnings Per Share	$1.543M	$1.139M	$6.39
COMMON SHARES
Basic Shares Outstanding	363.6M shares	379.5M shares	372.0M shares
Diluted Shares Outstanding			376.5M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$3.302B	$3.212B
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$2.282B	$2.214B	$2.214B
YoY Change	3.07%	1.28%	1.28%
Goodwill	$7.556B	$7.446B
YoY Change	1.48%	23.65%
Intangibles
YoY Change
Long-Term Investments	$2.899B	$2.882B	$2.882B
YoY Change	0.59%	29.47%	27.58%
Other Assets	$216.0M	$113.0M	$113.0M
YoY Change	91.15%	0.0%	0.0%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$245.6B	$244.6B	$244.6B
YoY Change	0.41%	2.6%	2.59%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$18.40B	$18.99B	$18.99B
YoY Change	-3.11%	95.28%	95.28%
Deferred Revenue
YoY Change
Short-Term Debt	$1.941B	$4.174B	$4.174B
YoY Change	-53.5%	4.72%	4.72%
Long-Term Debt Due	$41.00M
YoY Change
Total Short-Term Liabilities	$18.44B	$18.99B	$18.99B
YoY Change	-2.9%	95.28%	94.22%
LONG-TERM LIABILITIES
Long-Term Debt	$12.47B	$11.09B	$11.09B
YoY Change	12.4%	-4.54%	-4.1%
Other Long-Term Liabilities	$6.459B	$5.243B	$5.243B
YoY Change	23.19%	-10.86%	-10.86%
Total Long-Term Liabilities	$18.93B	$16.34B	$16.34B
YoY Change	15.86%	-6.66%	-6.38%
TOTAL LIABILITIES
Total Short-Term Liabilities	$18.44B	$18.99B	$18.99B
Total Long-Term Liabilities	$18.93B	$16.34B	$16.34B
Total Liabilities	$221.2B	$219.9B	$219.9B
YoY Change	0.6%	1.73%	1.74%
SHAREHOLDERS EQUITY
Retained Earnings	$21.92B	$20.55B
YoY Change	6.64%	9.27%
Common Stock	$504.0M	$504.0M
YoY Change	0.0%	0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$10.21B	$8.715B
YoY Change	17.14%	-3.48%
Treasury Stock Shares	146.5M shares	123.9M shares
Shareholders Equity	$24.43B	$24.74B	$24.74B
YoY Change
Total Liabilities & Shareholders Equity	$245.6B	$244.6B	$244.6B
YoY Change	0.41%	2.6%	2.59%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018
OPERATING ACTIVITIES
Net Income	$564.0M	$437.0M	$2.593B
YoY Change	29.06%	25.21%	20.27%
Depreciation, Depletion And Amortization	$363.0M	$329.0M	$599.0M
YoY Change	10.33%	13.84%	13.88%
Cash From Operating Activities	$1.053B	$1.114B	$10.18B
YoY Change	-5.48%	-78.08%	46.61%
INVESTING ACTIVITIES
Capital Expenditures	-$161.0M	-$173.0M	$609.0M
YoY Change	-6.94%	13.82%	-4.4%
Acquisitions			$2.595B
YoY Change
Other Investing Activities	-$5.362B	-$15.75B	-$76.00M
YoY Change	-65.96%	47.52%	-25.49%
Cash From Investing Activities	-$5.523B	-$15.93B	-$4.496B
YoY Change	-65.32%	47.05%	-9466.67%
FINANCING ACTIVITIES
Cash Dividend Paid			$828.0M
YoY Change			7.81%
Common Stock Issuance & Retirement, Net			-$800.0M
YoY Change			-161.92%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	4.174B	13.75B	-$4.471B
YoY Change	-69.63%	250.4%	-27.75%
NET CHANGE
Cash From Operating Activities	1.053B	1.114B	$10.18B
Cash From Investing Activities	-5.523B	-15.93B	-$4.496B
Cash From Financing Activities	4.174B	13.75B	-$4.471B
Net Change In Cash	-296.0M	-1.067B	$1.208B
YoY Change	-72.26%	-41.53%	51.0%
FREE CASH FLOW
Cash From Operating Activities	$1.053B	$1.114B	$10.18B
Capital Expenditures	-$161.0M	-$173.0M	$609.0M
Free Cash Flow	$1.214B	$1.287B	$9.566B
YoY Change	-5.67%	-75.42%	51.77%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000093751
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
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CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-07511
CY2020	dei	Entity Registrant Name EntityRegistrantName	STATE STREET CORPORATION
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MA
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	04-2456637
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	One Lincoln Street
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Boston,
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	MA
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	02111
CY2020	dei	City Area Code CityAreaCode	(617)
CY2020	dei	Local Phone Number LocalPhoneNumber	786-3000
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	No
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020Q2	dei	Entity Public Float EntityPublicFloat	22340000000	USD
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CY2020	stt	Fees And Commissions Foreign Exchange Trading Services FeesAndCommissionsForeignExchangeTradingServices	1363000000	USD
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CY2019	stt	Other Comprehensive Income Loss Expected Losses From Otti On Htm Securities Not From Credit Related Taxes OtherComprehensiveIncomeLossExpectedLossesFromOttiOnHtmSecuritiesNotFromCreditRelatedTaxes	1000000	USD
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CY2019	stt	Other Comprehensive Income Loss Expected Losses From Otti On Htm Securities Not From Credit Net Of Taxes OtherComprehensiveIncomeLossExpectedLossesFromOttiOnHtmSecuritiesNotFromCreditNetOfTaxes	1000000	USD
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CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	127000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	25000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	2806000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-33000000	USD
CY2020	stt	Other Comprehensive Income Loss Minimum Pension Liability Net Adjustment Tax OtherComprehensiveIncomeLossMinimumPensionLiabilityNetAdjustmentTax	3000000	USD
CY2019	stt	Other Comprehensive Income Loss Minimum Pension Liability Net Adjustment Tax OtherComprehensiveIncomeLossMinimumPensionLiabilityNetAdjustmentTax	-8000000	USD
CY2018	stt	Other Comprehensive Income Loss Minimum Pension Liability Net Adjustment Tax OtherComprehensiveIncomeLossMinimumPensionLiabilityNetAdjustmentTax	8000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-9000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	16000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-27000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	1063000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	564000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-347000000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	3483000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	2246000000	USD
CY2020Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	3467000000	USD
CY2019Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	3302000000	USD
CY2020Q4	us-gaap	Interest Bearing Deposits In Banks InterestBearingDepositsInBanks	116960000000	USD
CY2019Q4	stt	Debt Securities Heldtomaturity Purchased Under Money Market Facility DebtSecuritiesHeldtomaturityPurchasedUnderMoneyMarketFacility	0	USD
CY2019Q4	us-gaap	Interest Bearing Deposits In Banks InterestBearingDepositsInBanks	68965000000	USD
CY2020Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	3106000000	USD
CY2019Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	1487000000	USD
CY2020Q4	us-gaap	Trading Securities TradingSecurities	815000000	USD
CY2019Q4	us-gaap	Trading Securities TradingSecurities	914000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	59048000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	53815000000	USD
CY2020Q4	stt	Debt Securities Heldtomaturity Under Money Market Facility Allowancefor Credit Loss DebtSecuritiesHeldtomaturityUnderMoneyMarketFacilityAllowanceforCreditLoss	1000000	USD
CY2020Q4	stt	Debt Securities Heldtomaturity Under Money Market Facility Fair Value DebtSecuritiesHeldtomaturityUnderMoneyMarketFacilityFairValue	3304000000	USD
CY2020Q4	stt	Debt Securities Heldtomaturity Purchased Under Money Market Facility DebtSecuritiesHeldtomaturityPurchasedUnderMoneyMarketFacility	3299000000	USD
CY2020Q4	stt	Debt Securities Held To Maturity Allowance For Credit Loss Excluding Mmf DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingMMF	2000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	50003000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	42157000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	48929000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	41782000000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	122000000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	74000000	USD
CY2020Q4	us-gaap	Notes Receivable Net NotesReceivableNet	27803000000	USD
CY2019Q4	us-gaap	Notes Receivable Net NotesReceivableNet	26235000000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	4825000000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	4367000000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2154000000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2282000000	USD
CY2020Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	3105000000	USD
CY2019Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	3231000000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	7683000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	7556000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1827000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2030000000	USD
CY2020Q4	us-gaap	Other Assets OtherAssets	36510000000	USD
CY2019Q4	stt	Short Term Borrowings Under Money Market Liquidity Facility ShortTermBorrowingsUnderMoneyMarketLiquidityFacility	0	USD
CY2019Q4	us-gaap	Other Assets OtherAssets	34011000000	USD
CY2020Q4	us-gaap	Assets Assets	314706000000	USD
CY2019Q4	us-gaap	Assets Assets	245610000000	USD
CY2020Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	49439000000	USD
CY2019Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	34031000000	USD
CY2020Q4	us-gaap	Interest Bearing Deposit Liabilities Domestic InterestBearingDepositLiabilitiesDomestic	102331000000	USD
CY2019Q4	us-gaap	Interest Bearing Deposit Liabilities Domestic InterestBearingDepositLiabilitiesDomestic	77504000000	USD
CY2020Q4	us-gaap	Interest Bearing Deposit Liabilities Foreign InterestBearingDepositLiabilitiesForeign	88028000000	USD
CY2019Q4	us-gaap	Interest Bearing Deposit Liabilities Foreign InterestBearingDepositLiabilitiesForeign	70337000000	USD
CY2020Q4	us-gaap	Deposits Deposits	239798000000	USD
CY2019Q4	us-gaap	Deposits Deposits	181872000000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	3413000000	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	1102000000	USD
CY2020Q4	stt	Short Term Borrowings Under Money Market Liquidity Facility ShortTermBorrowingsUnderMoneyMarketLiquidityFacility	3302000000	USD
CY2020Q4	us-gaap	Other Short Term Borrowings OtherShortTermBorrowings	685000000	USD
CY2019Q4	us-gaap	Other Short Term Borrowings OtherShortTermBorrowings	839000000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	27503000000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	24857000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	13805000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	12509000000	USD
CY2020Q4	us-gaap	Liabilities Liabilities	288506000000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	221179000000	USD
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2020Q4	us-gaap	Preferred Stock No Par Value PreferredStockNoParValue	0
CY2019Q4	us-gaap	Preferred Stock No Par Value PreferredStockNoParValue	0
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	3500000	shares
CY2020Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1
CY2019Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	750000000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	503879642	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	503879642	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	353156279	shares
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	357389416	shares
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	504000000	USD
CY2019Q4	us-gaap	Common Stock Value CommonStockValue	504000000	USD
CY2020Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	10205000000	USD
CY2019Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	10132000000	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	23442000000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	21918000000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	187000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-876000000	USD
CY2020Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	150723363	shares
CY2019Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	146490226	shares
CY2020Q4	us-gaap	Treasury Stock Value TreasuryStockValue	10609000000	USD
CY2019Q4	us-gaap	Treasury Stock Value TreasuryStockValue	10209000000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	26200000000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	24431000000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	314706000000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	245610000000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	22270000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	2593000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-347000000	USD
CY2018	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	494000000	USD
CY2018	us-gaap	Stock Issued During Period Value Treasury Stock Reissued StockIssuedDuringPeriodValueTreasuryStockReissued	1150000000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.78
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	665000000	USD
CY2018	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	188000000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Par Value Method TreasuryStockValueAcquiredParValueMethod	350000000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	145000000	USD
CY2018	us-gaap	Stockholders Equity Other StockholdersEquityOther	365000000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	24737000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	2242000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	564000000	USD
CY2019	us-gaap	Stock Redeemed Or Called During Period Value StockRedeemedOrCalledDuringPeriodValue	750000000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.98
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	728000000	USD
CY2019	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	210000000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Par Value Method TreasuryStockValueAcquiredParValueMethod	1600000000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	198000000	USD
CY2019	us-gaap	Stockholders Equity Other StockholdersEquityOther	22000000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	24431000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	2420000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	1063000000	USD
CY2020	us-gaap	Stock Redeemed Or Called During Period Value StockRedeemedOrCalledDuringPeriodValue	500000000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.08
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	734000000	USD
CY2020	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	152000000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Par Value Method TreasuryStockValueAcquiredParValueMethod	500000000	USD
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	172000000	USD
CY2020	us-gaap	Stockholders Equity Other StockholdersEquityOther	0	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	26200000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	2420000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	2242000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	2593000000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-194000000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-130000000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-136000000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	234000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	236000000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	226000000	USD
CY2020	stt	Noncash Adjustments For Depreciation Amortization Accretion NoncashAdjustmentsForDepreciationAmortizationAccretion	1276000000	USD
CY2019	stt	Noncash Adjustments For Depreciation Amortization Accretion NoncashAdjustmentsForDepreciationAmortizationAccretion	1101000000	USD
CY2018	stt	Noncash Adjustments For Depreciation Amortization Accretion NoncashAdjustmentsForDepreciationAmortizationAccretion	977000000	USD
CY2020	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	4000000	USD
CY2019	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-1000000	USD
CY2018	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	6000000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	88000000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	10000000	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	15000000	USD
CY2020	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-99000000	USD
CY2019	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	54000000	USD
CY2018	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-233000000	USD
CY2020	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	-127000000	USD
CY2019	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	28000000	USD
CY2018	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	-26000000	USD
CY2020	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	-2951000000	USD
CY2019	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	287000000	USD
CY2018	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	7326000000	USD
CY2020	stt	Change In Unrealized Gains Losses Related To Financial Instruments ChangeInUnrealizedGainsLossesRelatedToFinancialInstruments	-3652000000	USD
CY2019	stt	Change In Unrealized Gains Losses Related To Financial Instruments ChangeInUnrealizedGainsLossesRelatedToFinancialInstruments	-2034000000	USD
CY2018	stt	Change In Unrealized Gains Losses Related To Financial Instruments ChangeInUnrealizedGainsLossesRelatedToFinancialInstruments	1836000000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	1406000000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	713000000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	22000000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-170000000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	294000000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	394000000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-361000000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-410000000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-385000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3532000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	5690000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	10175000000	USD
CY2020	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	-47995000000	USD
CY2020	us-gaap	Payments To Acquire Loans And Leases Held For Investment PaymentsToAcquireLoansAndLeasesHeldForInvestment	1939000000	USD
CY2018	stt	Purchases Under Money Market Liquidity Facility PurchasesUnderMoneyMarketLiquidityFacility	0	USD
CY2020	stt	Proceeds From Under Money Market Liquidity Facility ProceedsFromUnderMoneyMarketLiquidityFacility	25984000000	USD
CY2019	stt	Proceeds From Under Money Market Liquidity Facility ProceedsFromUnderMoneyMarketLiquidityFacility	0	USD
CY2018	stt	Proceeds From Under Money Market Liquidity Facility ProceedsFromUnderMoneyMarketLiquidityFacility	0	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	15179000000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	10390000000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	6296000000	USD
CY2020	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	13981000000	USD
CY2019	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	6938000000	USD
CY2018	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	6539000000	USD
CY2020	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	324000000	USD
CY2019	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	131000000	USD
CY2018	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	278000000	USD
CY2019	us-gaap	Payments To Acquire Loans And Leases Held For Investment PaymentsToAcquireLoansAndLeasesHeldForInvestment	650000000	USD
CY2018	us-gaap	Payments To Acquire Loans And Leases Held For Investment PaymentsToAcquireLoansAndLeasesHeldForInvestment	2739000000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	4075000000	USD
CY2018	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	-5813000000	USD
CY2020	stt	Net Increase Decrease In Federal Funds Sold And Securities Purchased Under Resale Agreements NetIncreaseDecreaseInFederalFundsSoldAndSecuritiesPurchasedUnderResaleAgreements	-1619000000	USD
CY2019	stt	Net Increase Decrease In Federal Funds Sold And Securities Purchased Under Resale Agreements NetIncreaseDecreaseInFederalFundsSoldAndSecuritiesPurchasedUnderResaleAgreements	3192000000	USD
CY2018	stt	Net Increase Decrease In Federal Funds Sold And Securities Purchased Under Resale Agreements NetIncreaseDecreaseInFederalFundsSoldAndSecuritiesPurchasedUnderResaleAgreements	-1438000000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2645000000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	5642000000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	26082000000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	23644000000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	20407000000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	14645000000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	37873000000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	38164000000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	31814000000	USD
CY2020	stt	Purchases Under Money Market Liquidity Facility PurchasesUnderMoneyMarketLiquidityFacility	29242000000	USD
CY2019	stt	Purchases Under Money Market Liquidity Facility PurchasesUnderMoneyMarketLiquidityFacility	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	54000000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	2595000000	USD
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	1436000000	USD
CY2019	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	647000000	USD
CY2018	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	326000000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	560000000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	730000000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	609000000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-1335000000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-720000000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-76000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-65534000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2626000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-4496000000	USD
CY2020	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-33466000000	USD
CY2019	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-11255000000	USD
CY2018	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	6673000000	USD
CY2020	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	91391000000	USD
CY2019	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	12767000000	USD
CY2018	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	-11209000000	USD
CY2020	stt	Securities Sold Under Repurchase Agreement Net SecuritiesSoldUnderRepurchaseAgreementNet	2311000000	USD
CY2019	stt	Securities Sold Under Repurchase Agreement Net SecuritiesSoldUnderRepurchaseAgreementNet	20000000	USD
CY2018	stt	Securities Sold Under Repurchase Agreement Net SecuritiesSoldUnderRepurchaseAgreementNet	-1760000000	USD
CY2020	stt	Net Decrease Increase In Other Short Term Borrowings NetDecreaseIncreaseInOtherShortTermBorrowings	-154000000	USD
CY2019	stt	Net Decrease Increase In Other Short Term Borrowings NetDecreaseIncreaseInOtherShortTermBorrowings	-2253000000	USD
CY2018	stt	Net Decrease Increase In Other Short Term Borrowings NetDecreaseIncreaseInOtherShortTermBorrowings	1948000000	USD
CY2020	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	3302000000	USD
CY2019	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	0	USD
CY2018	us-gaap	Proceeds From Short Term Debt ProceedsFromShortTermDebt	0	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	2489000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1495000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	995000000	USD
CY2020	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	1724000000	USD
CY2019	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	402000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	1461000000	USD
CY2020	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	500000000	USD
CY2019	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	750000000	USD
CY2018	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	USD
CY2020	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	495000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	1150000000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	515000000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1585000000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	350000000	USD
CY2020	stt	Repurchases Of Common Stock For Employee Tax Withholding RepurchasesOfCommonStockForEmployeeTaxWithholding	78000000	USD
CY2019	stt	Repurchases Of Common Stock For Employee Tax Withholding RepurchasesOfCommonStockForEmployeeTaxWithholding	81000000	USD
CY2018	stt	Repurchases Of Common Stock For Employee Tax Withholding RepurchasesOfCommonStockForEmployeeTaxWithholding	124000000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	889000000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	930000000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	828000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	62167000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2974000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-4471000000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	165000000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	90000000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	1208000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	3302000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	3212000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2004000000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	3467000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	3302000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	3212000000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	375000000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	1382000000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	981000000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	403000000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	510000000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	549000000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	line_of_business
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:3pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions in the application of certain of our significant accounting policies that may materially affect the reported amounts of assets, liabilities, equity, revenue and expenses. As a result of unanticipated events or circumstances, actual results could differ from those estimates.</span></div>
CY2020Q4	stt	Derivative Asset Collateral Obligationto Return Securitiesand Cash Offset DerivativeAssetCollateralObligationtoReturnSecuritiesandCashOffset	5870000000	USD
CY2020Q4	stt	Derivative Liability Collateral Rightto Reclaim Securitiesand Cash Offset DerivativeLiabilityCollateralRighttoReclaimSecuritiesandCashOffset	1290000000	USD
CY2019Q4	stt	Derivative Asset Collateral Obligationto Return Securitiesand Cash Offset DerivativeAssetCollateralObligationtoReturnSecuritiesandCashOffset	2310000000	USD
CY2019Q4	stt	Derivative Liability Collateral Rightto Reclaim Securitiesand Cash Offset DerivativeLiabilityCollateralRighttoReclaimSecuritiesandCashOffset	840000000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	2756000000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-6000000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	27000000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	870000000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	95000000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	83000000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	50000000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	3503000000	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	16000000	USD
CY2020	stt	Change In Unrealized Gains Losses Related To Financial Instruments Assets Held At Period End ChangeInUnrealizedGainsLossesRelatedToFinancialInstrumentsAssetsHeldAtPeriodEnd	-3000000	USD
CY2018Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	1288000000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-14000000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-10000000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	1544000000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	381000000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	503000000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	174000000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	2756000000	USD
CY2019	stt	Change In Unrealized Gains Losses Related To Financial Instruments Assets Held At Period End ChangeInUnrealizedGainsLossesRelatedToFinancialInstrumentsAssetsHeldAtPeriodEnd	-11000000	USD
CY2020Q4	stt	Short Term Borrowings Under Money Market Liquidity Facility ShortTermBorrowingsUnderMoneyMarketLiquidityFacility	3302000000	USD
CY2020Q1	stt	Debt Securities Heldtomaturity Purchased Under Money Market Facility DebtSecuritiesHeldtomaturityPurchasedUnderMoneyMarketFacility	29000000000	USD
CY2020Q4	stt	Debt Securities Heldtomaturity Purchased Under Money Market Facility DebtSecuritiesHeldtomaturityPurchasedUnderMoneyMarketFacility	3300000000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	3000000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	57987000000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	1087000000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	26000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	59048000000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	53314000000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	575000000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	74000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	53815000000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	3000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	53000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	4894000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	42000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	13570000000	USD
CY2020Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	70570000000	USD
CY2019Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	49480000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	7490000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	19000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1351000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	7000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	8841000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	26000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	12428000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	50000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	2626000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	24000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	15054000000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	74000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	8676000000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	95000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	7612000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	7644000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	27242000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	27656000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	9403000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	9632000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	13730000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	14116000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	57987000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	59048000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	7902000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	7946000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	3421000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	3478000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	5724000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	5860000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	35184000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	36023000000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	52231000000	USD
CY2019	us-gaap	Impairment Of Investments ImpairmentOfInvestments	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	53307000000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	31000000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	205000000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	32000000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	196000000	USD
CY2019	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	0	USD
CY2018	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	-3000000	USD
CY2019	us-gaap	Impairment Of Investments ImpairmentOfInvestments	0	USD
CY2018	us-gaap	Impairment Of Investments ImpairmentOfInvestments	3000000	USD
CY2019	us-gaap	Marketable Securities Gain Loss MarketableSecuritiesGainLoss	-1000000	USD
CY2018	us-gaap	Marketable Securities Gain Loss MarketableSecuritiesGainLoss	6000000	USD
CY2019	stt	Impairment Associated With Adverse Changes In Timing Of Expected Future Cash Flows ImpairmentAssociatedWithAdverseChangesInTimingOfExpectedFutureCashFlows	0	USD
CY2018	stt	Impairment Associated With Adverse Changes In Timing Of Expected Future Cash Flows ImpairmentAssociatedWithAdverseChangesInTimingOfExpectedFutureCashFlows	3000000	USD
CY2018	us-gaap	Impairment Of Investments ImpairmentOfInvestments	3000000	USD
CY2020Q4	stt	Percentageof Portfolio Considered Investment Grade PercentageofPortfolioConsideredInvestmentGrade	0.99
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	3000000	USD
CY2020	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss Writeoff DebtSecuritiesHeldToMaturityAllowanceForCreditLossWriteoff	0	USD
CY2020	us-gaap	Marketable Securities Unrealized Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesUnrealizedGainLossExcludingOtherThanTemporaryImpairments	-123000000	USD
CY2020	stt	Available For Sale And Held To Maturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions AvailableForSaleAndHeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions	503	security
CY2018	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	-3000000	USD
CY2019Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	78000000	USD
CY2018Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	77000000	USD
CY2020	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment	0	USD
CY2019	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment	3000000	USD
CY2020	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	8000000	USD
CY2019	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	2000000	USD
CY2020Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	70000000	USD
CY2019Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	78000000	USD
CY2020	us-gaap	Marketable Securities Unrealized Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesUnrealizedGainLossExcludingOtherThanTemporaryImpairments	-123000000	USD
CY2019	stt	Available For Sale And Held To Maturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions AvailableForSaleAndHeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions	622	security
CY2019	us-gaap	Marketable Securities Unrealized Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesUnrealizedGainLossExcludingOtherThanTemporaryImpairments	-169000000	USD
CY2020	stt	Available For Sale And Held To Maturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions AvailableForSaleAndHeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions	503	security
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	27925000000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	26309000000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	122000000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	74000000	USD
CY2020Q4	us-gaap	Notes Receivable Net NotesReceivableNet	27803000000	USD
CY2019Q4	us-gaap	Notes Receivable Net NotesReceivableNet	26235000000	USD
CY2020	stt	Loans And Leases Receivable Number Of Loans And Leases Segments LoansAndLeasesReceivableNumberOfLoansAndLeasesSegments	2	loan_segment
CY2020Q4	us-gaap	Loans Pledged As Collateral LoansPledgedAsCollateral	8070000000.00	USD
CY2019Q4	us-gaap	Loans Pledged As Collateral LoansPledgedAsCollateral	6750000000	USD
CY2020Q4	stt	Financing Receivable Recorded Investment Nonaccrual Status Numberof Loans FinancingReceivableRecordedInvestmentNonaccrualStatusNumberofLoans	0	loan
CY2019Q4	stt	Financing Receivable Recorded Investment Nonaccrual Status Numberof Loans FinancingReceivableRecordedInvestmentNonaccrualStatusNumberofLoans	0	loan
CY2020Q4	stt	Financing Receivable Recorded Investment Equal To30 Days Or Greater FinancingReceivableRecordedInvestmentEqualTo30DaysOrGreater	1	loan
CY2019Q4	stt	Financing Receivable Recorded Investment Equal To30 Days Or Greater FinancingReceivableRecordedInvestmentEqualTo30DaysOrGreater	0	loan
CY2020	us-gaap	Gain Loss On Sale Of Notes Receivable GainLossOnSaleOfNotesReceivable	-41000000	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	0	loan
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	0	loan
CY2020Q4	stt	Numberof Loans No Longer Met Similar Risk NumberofLoansNoLongerMetSimilarRisk	5	loan
CY2020Q4	stt	Loans No Longer Meeting Similar Riskof Collective Pool LoansNoLongerMeetingSimilarRiskofCollectivePool	77000000	USD
CY2019Q4	stt	Numberof Loans No Longer Met Similar Risk NumberofLoansNoLongerMetSimilarRisk	1	loan
CY2019Q4	stt	Loans No Longer Meeting Similar Riskof Collective Pool LoansNoLongerMeetingSimilarRiskofCollectivePool	25000000	USD
CY2020Q4	stt	Investment Grade Loans InvestmentGradeLoans	0.81
CY2020Q4	stt	Speculative Grade Loans SpeculativeGradeLoans	0.19
CY2020Q4	stt	Speculative Senior Secured Loanswith B Bor B Rating SpeculativeSeniorSecuredLoanswithBBorBRating	0.85
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	27925000000	USD
CY2020Q4	us-gaap	Financing Receivable Originated In Current Fiscal Year FinancingReceivableOriginatedInCurrentFiscalYear	3935000000	USD
CY2020Q4	us-gaap	Financing Receivable Originated In Fiscal Year Before Latest Fiscal Year FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear	2313000000	USD
CY2020Q4	us-gaap	Financing Receivable Originated Two Years Before Latest Fiscal Year FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear	1918000000	USD
CY2020Q4	us-gaap	Financing Receivable Originated Three Years Before Latest Fiscal Year FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear	1272000000	USD
CY2020Q4	us-gaap	Financing Receivable Originated Four Years Before Latest Fiscal Year FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear	495000000	USD
CY2020Q4	stt	Financing Receivable Originated More Than Five Yearsbefore Latest Fiscal Year FinancingReceivableOriginatedMoreThanFiveYearsbeforeLatestFiscalYear	95000000	USD
CY2020Q4	us-gaap	Financing Receivable Revolving FinancingReceivableRevolving	17897000000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	27925000000	USD
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	72000000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	88000000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	67000000	USD
CY2017Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	54000000	USD
CY2019	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	10000000	USD
CY2018	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	15000000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	3000000	USD
CY2018	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	2000000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	74000000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	67000000	USD
CY2018	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2020	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2019	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2018Q4	us-gaap	Goodwill Goodwill	7446000000	USD
CY2019	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	122000000	USD
CY2019	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	-12000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	7556000000	USD
CY2020	us-gaap	Goodwill Translation And Purchase Accounting Adjustments GoodwillTranslationAndPurchaseAccountingAdjustments	127000000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	7683000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2369000000	USD
CY2019	us-gaap	Finite Lived Intangible Assets Purchase Accounting Adjustments FiniteLivedIntangibleAssetsPurchaseAccountingAdjustments	-93000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	236000000	USD
CY2019	us-gaap	Finite Lived Intangible Assets Foreign Currency Translation Gain Loss FiniteLivedIntangibleAssetsForeignCurrencyTranslationGainLoss	-10000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2030000000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	234000000	USD
CY2020	us-gaap	Finite Lived Intangible Assets Foreign Currency Translation Gain Loss FiniteLivedIntangibleAssetsForeignCurrencyTranslationGainLoss	31000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1827000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	3894000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	2067000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1827000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	4280000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	2250000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2030000000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	234000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	236000000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	226000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	235000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	232000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	231000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	224000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	199000000	USD
CY2020Q4	stt	Securities Borrowed Subject To Master Netting Arrangements SecuritiesBorrowedSubjectToMasterNettingArrangements	18330000000	USD
CY2019Q4	stt	Securities Borrowed Subject To Master Netting Arrangements SecuritiesBorrowedSubjectToMasterNettingArrangements	18524000000	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	5804000000	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	4753000000	USD
CY2020Q4	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	3479000000	USD
CY2019Q4	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	3395000000	USD
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	3095000000	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	2899000000	USD
CY2020Q4	us-gaap	Deposit Liabilities Collateral Issued Financial Instruments DepositLiabilitiesCollateralIssuedFinancialInstruments	2713000000	USD
CY2019Q4	us-gaap	Deposit Liabilities Collateral Issued Financial Instruments DepositLiabilitiesCollateralIssuedFinancialInstruments	874000000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	720000000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	858000000	USD
CY2020Q4	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	383000000	USD
CY2019Q4	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	395000000	USD
CY2020Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	379000000	USD
CY2019Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	432000000	USD
CY2020Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	367000000	USD
CY2019Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	309000000	USD
CY2020Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	233000000	USD
CY2019Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	216000000	USD
CY2020Q4	stt	Receivable For Security Settlement ReceivableForSecuritySettlement	117000000	USD
CY2019Q4	stt	Receivable For Security Settlement ReceivableForSecuritySettlement	336000000	USD
CY2020Q4	us-gaap	Deposits With Clearing Organizations And Others Securities DepositsWithClearingOrganizationsAndOthersSecurities	58000000	USD
CY2019Q4	us-gaap	Deposits With Clearing Organizations And Others Securities DepositsWithClearingOrganizationsAndOthersSecurities	58000000	USD
CY2020Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	832000000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous OtherAssetsMiscellaneous	962000000	USD
CY2020Q4	us-gaap	Other Assets OtherAssets	36510000000	USD
CY2019Q4	us-gaap	Other Assets OtherAssets	34011000000	USD
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	1680000000	USD
CY2019Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	35150000000	USD
CY2020Q4	stt	Time Deposits Overdrafts TimeDepositsOverdrafts	2980000000	USD
CY2019Q4	stt	Time Deposits Overdrafts TimeDepositsOverdrafts	3260000000	USD
CY2020Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0093
CY2019Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.0164
CY2020Q4	stt	Average Balances Of Securities Purchased Under Agreements To Resell And Securities Sold Under Agreements To Repurchase AverageBalancesOfSecuritiesPurchasedUnderAgreementsToResellAndSecuritiesSoldUnderAgreementsToRepurchase	100450000000	USD
CY2019Q4	stt	Average Balances Of Securities Purchased Under Agreements To Resell And Securities Sold Under Agreements To Repurchase AverageBalancesOfSecuritiesPurchasedUnderAgreementsToResellAndSecuritiesSoldUnderAgreementsToRepurchase	86670000000	USD
CY2020Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	1400000000	CAD
CY2020Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	1100000000	USD
CY2020Q4	us-gaap	Line Of Credit LineOfCredit	0	USD
CY2019Q4	us-gaap	Line Of Credit LineOfCredit	0	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	13805000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Including Current Maturities LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities	12509000000	USD
CY2020	us-gaap	Change In Unrealized Gain Loss On Fair Value Hedging Instruments1 ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1	567000000	USD
CY2019	us-gaap	Change In Unrealized Gain Loss On Fair Value Hedging Instruments1 ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1	262000000	USD
CY2018	us-gaap	Change In Unrealized Gain Loss On Fair Value Hedging Instruments1 ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1	-429000000	USD
CY2020	us-gaap	Change In Unrealized Gain Loss On Hedged Item In Fair Value Hedge1 ChangeInUnrealizedGainLossOnHedgedItemInFairValueHedge1	-563000000	USD
CY2019	us-gaap	Change In Unrealized Gain Loss On Hedged Item In Fair Value Hedge1 ChangeInUnrealizedGainLossOnHedgedItemInFairValueHedge1	-253000000	USD
CY2018	us-gaap	Change In Unrealized Gain Loss On Hedged Item In Fair Value Hedge1 ChangeInUnrealizedGainLossOnHedgedItemInFairValueHedge1	419000000	USD
CY2020	stt	Other Comprehensive Income Loss Securities Available For Sale Designated In Fair Value Hedges Unrealized Holding Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossSecuritiesAvailableForSaleDesignatedInFairValueHedgesUnrealizedHoldingGainLossArisingDuringPeriodAfterTax	3000000	USD
CY2019	stt	Other Comprehensive Income Loss Securities Available For Sale Designated In Fair Value Hedges Unrealized Holding Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossSecuritiesAvailableForSaleDesignatedInFairValueHedgesUnrealizedHoldingGainLossArisingDuringPeriodAfterTax	18000000	USD
CY2018	stt	Other Comprehensive Income Loss Securities Available For Sale Designated In Fair Value Hedges Unrealized Holding Gain Loss Arising During Period After Tax OtherComprehensiveIncomeLossSecuritiesAvailableForSaleDesignatedInFairValueHedgesUnrealizedHoldingGainLossArisingDuringPeriodAfterTax	24000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	154000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	51000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-24000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	72000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	17000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	26000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax	-250000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax	30000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossBeforeReclassificationAndTax	81000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossReclassificationBeforeTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossReclassificationBeforeTax	0	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Investment Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossNetInvestmentHedgeGainLossReclassificationBeforeTax	0	USD
CY2020	stt	Other Comprehensive Income Loss Derivative Before Reclassification And Tax OtherComprehensiveIncomeLossDerivativeBeforeReclassificationAndTax	-96000000	USD
CY2019	stt	Other Comprehensive Income Loss Derivative Before Reclassification And Tax OtherComprehensiveIncomeLossDerivativeBeforeReclassificationAndTax	81000000	USD
CY2018	stt	Other Comprehensive Income Loss Derivative Before Reclassification And Tax OtherComprehensiveIncomeLossDerivativeBeforeReclassificationAndTax	57000000	USD
CY2020	stt	Other Comprehensive Income Loss Derivative Gain Loss Reclassificationbefore Tax OtherComprehensiveIncomeLossDerivativeGainLossReclassificationbeforeTax	72000000	USD
CY2019	stt	Other Comprehensive Income Loss Derivative Gain Loss Reclassificationbefore Tax OtherComprehensiveIncomeLossDerivativeGainLossReclassificationbeforeTax	17000000	USD
CY2018	stt	Other Comprehensive Income Loss Derivative Gain Loss Reclassificationbefore Tax OtherComprehensiveIncomeLossDerivativeGainLossReclassificationbeforeTax	26000000	USD
CY2020Q4	us-gaap	Fair Value Of Securities Received As Collateral That Can Be Resold Or Repledged FairValueOfSecuritiesReceivedAsCollateralThatCanBeResoldOrRepledged	6480000000	USD
CY2019Q4	us-gaap	Fair Value Of Securities Received As Collateral That Can Be Resold Or Repledged FairValueOfSecuritiesReceivedAsCollateralThatCanBeResoldOrRepledged	10090000000.00	USD
CY2020Q4	us-gaap	Fair Value Of Securities Received As Collateral That Have Been Resold Or Repledged FairValueOfSecuritiesReceivedAsCollateralThatHaveBeenResoldOrRepledged	3880000000	USD
CY2019Q4	us-gaap	Fair Value Of Securities Received As Collateral That Have Been Resold Or Repledged FairValueOfSecuritiesReceivedAsCollateralThatHaveBeenResoldOrRepledged	5720000	USD
CY2020Q4	stt	Derivative Asset Collateral Obligationto Return Securitiesand Cash Offset DerivativeAssetCollateralObligationtoReturnSecuritiesandCashOffset	5869000000	USD
CY2020Q4	stt	Derivative Asset Collateral Obligationto Return Securitiesand Cash Offset DerivativeAssetCollateralObligationtoReturnSecuritiesandCashOffset	5869000000	USD
CY2020Q4	stt	Derivative Collateral Obligationto Return Securitiesand Cash DerivativeCollateralObligationtoReturnSecuritiesandCash	1105000000	USD
CY2020Q4	stt	Derivative Collateral Obligationto Return Securitiesand Cash Netof Offset DerivativeCollateralObligationtoReturnSecuritiesandCashNetofOffset	6974000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	25944000000	USD
CY2020Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	20140000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	5804000000	USD
CY2020Q4	stt	Derivative Collateral Obligationto Return Securitiesand Cash DerivativeCollateralObligationtoReturnSecuritiesandCash	1105000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	4699000000	USD
CY2020Q4	stt	Reverse Repurchase Agreements And Securities Borrowing Fair Value Gross Asset ReverseRepurchaseAgreementsAndSecuritiesBorrowingFairValueGrossAsset	174461000000	USD
CY2020Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Liability ReverseRepurchaseAgreementsAndSecuritiesBorrowedLiability	153025000000	USD
CY2020Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Fair Value Amount Not Offset Against Collateral ReverseRepurchaseAgreementsAndSecuritiesBorrowedFairValueAmountNotOffsetAgainstCollateral	21436000000	USD
CY2020Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Collateral Obligation To Return Cash ReverseRepurchaseAgreementsAndSecuritiesBorrowedCollateralObligationToReturnCash	20568000000	USD
CY2020Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Amount Offset Against Collateral ReverseRepurchaseAgreementsAndSecuritiesBorrowedAmountOffsetAgainstCollateral	868000000	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Gross DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedGross	200405000000	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Liability DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedLiability	173165000000	USD
CY2020Q4	stt	Derivative Asset Reverse Repurchase Agreements And Securities Borrowed Not Offset Against Collateral DerivativeAssetReverseRepurchaseAgreementsAndSecuritiesBorrowedNotOffsetAgainstCollateral	27240000000	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Collateral Obligation To Return Cash DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedCollateralObligationToReturnCash	21673000000	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Amount Offset Against Collateral DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedAmountOffsetAgainstCollateral	5567000000	USD
CY2019Q4	stt	Derivative Asset Collateral Obligationto Return Securitiesand Cash Offset DerivativeAssetCollateralObligationtoReturnSecuritiesandCashOffset	2310000000	USD
CY2019Q4	stt	Derivative Asset Collateral Obligationto Return Securitiesand Cash Offset DerivativeAssetCollateralObligationtoReturnSecuritiesandCashOffset	2310000000	USD
CY2019Q4	stt	Derivative Collateral Obligationto Return Securitiesand Cash DerivativeCollateralObligationtoReturnSecuritiesandCash	685000000	USD
CY2019Q4	stt	Derivative Collateral Obligationto Return Securitiesand Cash Netof Offset DerivativeCollateralObligationtoReturnSecuritiesandCashNetofOffset	2995000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	15148000000	USD
CY2019Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	10395000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	4753000000	USD
CY2019Q4	stt	Derivative Collateral Obligationto Return Securitiesand Cash DerivativeCollateralObligationtoReturnSecuritiesandCash	685000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	4068000000	USD
CY2019Q4	stt	Reverse Repurchase Agreements And Securities Borrowing Fair Value Gross Asset ReverseRepurchaseAgreementsAndSecuritiesBorrowingFairValueGrossAsset	179989000000	USD
CY2019Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Liability ReverseRepurchaseAgreementsAndSecuritiesBorrowedLiability	159978000000	USD
CY2019Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Fair Value Amount Not Offset Against Collateral ReverseRepurchaseAgreementsAndSecuritiesBorrowedFairValueAmountNotOffsetAgainstCollateral	20011000000	USD
CY2019Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Collateral Obligation To Return Cash ReverseRepurchaseAgreementsAndSecuritiesBorrowedCollateralObligationToReturnCash	19572000000	USD
CY2019Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Amount Offset Against Collateral ReverseRepurchaseAgreementsAndSecuritiesBorrowedAmountOffsetAgainstCollateral	439000000	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Gross DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedGross	195137000000	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Liability DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedLiability	170373000000	USD
CY2019Q4	stt	Derivative Asset Reverse Repurchase Agreements And Securities Borrowed Not Offset Against Collateral DerivativeAssetReverseRepurchaseAgreementsAndSecuritiesBorrowedNotOffsetAgainstCollateral	24764000000	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Collateral Obligation To Return Cash DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedCollateralObligationToReturnCash	20257000000	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Amount Offset Against Collateral DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedAmountOffsetAgainstCollateral	4507000000	USD
CY2020Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Fair Value Amount Not Offset Against Collateral ReverseRepurchaseAgreementsAndSecuritiesBorrowedFairValueAmountNotOffsetAgainstCollateral	21440000000	USD
CY2020Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	3110000000	USD
CY2020Q4	us-gaap	Cash Collateral For Borrowed Securities CashCollateralForBorrowedSecurities	18330000000	USD
CY2019Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Fair Value Amount Not Offset Against Collateral ReverseRepurchaseAgreementsAndSecuritiesBorrowedFairValueAmountNotOffsetAgainstCollateral	20010000000.00	USD
CY2019Q4	us-gaap	Securities Purchased Under Agreements To Resell SecuritiesPurchasedUnderAgreementsToResell	1490000000	USD
CY2019Q4	us-gaap	Cash Collateral For Borrowed Securities CashCollateralForBorrowedSecurities	18520000000	USD
CY2020Q4	stt	Derivative Liability Collateral Rightto Reclaim Securitiesand Cash Offset DerivativeLiabilityCollateralRighttoReclaimSecuritiesandCashOffset	1287000000	USD
CY2020Q4	stt	Derivative Liability Collateral Rightto Reclaim Securitiesand Cash Offset DerivativeLiabilityCollateralRighttoReclaimSecuritiesandCashOffset	1287000000	USD
CY2020Q4	stt	Derivative Collateral Rightto Reclaim Securitiesand Cash DerivativeCollateralRighttoReclaimSecuritiesandCash	1732000000	USD
CY2020Q4	stt	Derivative Collateral Rightto Reclaim Securitiesand Cash Netof Offset DerivativeCollateralRighttoReclaimSecuritiesandCashNetofOffset	3019000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	26126000000	USD
CY2020Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	15558000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	10568000000	USD
CY2020Q4	stt	Derivative Collateral Rightto Reclaim Securitiesand Cash DerivativeCollateralRighttoReclaimSecuritiesandCash	1732000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	8836000000	USD
CY2020Q4	stt	Reverse Repurchase Agreements And Securities Borrowing Fair Value Gross Liability ReverseRepurchaseAgreementsAndSecuritiesBorrowingFairValueGrossLiability	165793000000	USD
CY2020Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Asset ReverseRepurchaseAgreementsAndSecuritiesBorrowedAsset	153025000000	USD
CY2020Q4	stt	Repurchase Agreements And Securities Lending Fair Value Amount Not Offset Against Collateral RepurchaseAgreementsAndSecuritiesLendingFairValueAmountNotOffsetAgainstCollateral	12768000000	USD
CY2020Q4	stt	Repurchase Agreements And Securities Loaned Collateral Right To Reclaim Cash RepurchaseAgreementsAndSecuritiesLoanedCollateralRightToReclaimCash	12448000000	USD
CY2020Q4	stt	Repurchase Agreements And Securities Loaned Amount Offset Against Collateral RepurchaseAgreementsAndSecuritiesLoanedAmountOffsetAgainstCollateral	320000000	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Gross DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedGross	191919000000	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Asset DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAsset	168583000000	USD
CY2020Q4	stt	Derivative Liability Securities Sold Under Agreements To Resell And Securities Loaned Not Offset Against Collateral DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellAndSecuritiesLoanedNotOffsetAgainstCollateral	23336000000	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Collateral Right To Reclaim Cash DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedCollateralRightToReclaimCash	14180000000	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Amount Offset Against Collateral DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAmountOffsetAgainstCollateral	9156000000	USD
CY2019Q4	stt	Derivative Liability Collateral Rightto Reclaim Securitiesand Cash Offset DerivativeLiabilityCollateralRighttoReclaimSecuritiesandCashOffset	837000000	USD
CY2019Q4	stt	Derivative Liability Collateral Rightto Reclaim Securitiesand Cash Offset DerivativeLiabilityCollateralRighttoReclaimSecuritiesandCashOffset	837000000	USD
CY2019Q4	stt	Derivative Collateral Rightto Reclaim Securitiesand Cash DerivativeCollateralRighttoReclaimSecuritiesandCash	557000000	USD
CY2019Q4	stt	Derivative Collateral Rightto Reclaim Securitiesand Cash Netof Offset DerivativeCollateralRighttoReclaimSecuritiesandCashNetofOffset	1394000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	15381000000	USD
CY2019Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	8922000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	6459000000	USD
CY2019Q4	stt	Derivative Collateral Rightto Reclaim Securitiesand Cash DerivativeCollateralRighttoReclaimSecuritiesandCash	557000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	5902000000	USD
CY2019Q4	stt	Reverse Repurchase Agreements And Securities Borrowing Fair Value Gross Liability ReverseRepurchaseAgreementsAndSecuritiesBorrowingFairValueGrossLiability	171853000000	USD
CY2019Q4	stt	Reverse Repurchase Agreements And Securities Borrowed Asset ReverseRepurchaseAgreementsAndSecuritiesBorrowedAsset	159977000000	USD
CY2019Q4	stt	Repurchase Agreements And Securities Lending Fair Value Amount Not Offset Against Collateral RepurchaseAgreementsAndSecuritiesLendingFairValueAmountNotOffsetAgainstCollateral	11876000000	USD
CY2019Q4	stt	Repurchase Agreements And Securities Loaned Collateral Right To Reclaim Cash RepurchaseAgreementsAndSecuritiesLoanedCollateralRightToReclaimCash	10793000000	USD
CY2019Q4	stt	Repurchase Agreements And Securities Loaned Amount Offset Against Collateral RepurchaseAgreementsAndSecuritiesLoanedAmountOffsetAgainstCollateral	1083000000	USD
CY2019Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Gross DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedGross	187234000000	USD
CY2019Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Asset DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAsset	168899000000	USD
CY2019Q4	stt	Derivative Liability Securities Sold Under Agreements To Resell And Securities Loaned Not Offset Against Collateral DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellAndSecuritiesLoanedNotOffsetAgainstCollateral	18335000000	USD
CY2019Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Collateral Right To Reclaim Cash DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedCollateralRightToReclaimCash	11350000000	USD
CY2019Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Amount Offset Against Collateral DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAmountOffsetAgainstCollateral	6985000000	USD
CY2020Q4	stt	Repurchase Agreements And Securities Lending Fair Value Amount Not Offset Against Collateral RepurchaseAgreementsAndSecuritiesLendingFairValueAmountNotOffsetAgainstCollateral	12770000000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	3410000000	USD
CY2019Q4	stt	Repurchase Agreements And Securities Lending Fair Value Amount Not Offset Against Collateral RepurchaseAgreementsAndSecuritiesLendingFairValueAmountNotOffsetAgainstCollateral	11880000000	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	1100000000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase Gross SecuritiesSoldUnderAgreementsToRepurchaseGross	152140000000	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase Gross SecuritiesSoldUnderAgreementsToRepurchaseGross	156465000000	USD
CY2020Q4	us-gaap	Securities Loaned Gross SecuritiesLoanedGross	13653000000	USD
CY2019Q4	us-gaap	Securities Loaned Gross SecuritiesLoanedGross	15388000000	USD
CY2020Q4	us-gaap	Securities Loaned And Securities Sold Under Agreement To Repurchase Gross Including Not Subject To Master Netting Arrangement SecuritiesLoanedAndSecuritiesSoldUnderAgreementToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement	165793000000	USD
CY2019Q4	us-gaap	Securities Loaned And Securities Sold Under Agreement To Repurchase Gross Including Not Subject To Master Netting Arrangement SecuritiesLoanedAndSecuritiesSoldUnderAgreementToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement	171853000000	USD
CY2020Q4	us-gaap	Unused Commitments To Extend Credit UnusedCommitmentsToExtendCredit	34213000000	USD
CY2019Q4	us-gaap	Unused Commitments To Extend Credit UnusedCommitmentsToExtendCredit	29697000000	USD
CY2020Q4	stt	Aggregate Fair Value Of Indemnified Securities On Loan AggregateFairValueOfIndemnifiedSecuritiesOnLoan	440875000000	USD
CY2019Q4	stt	Aggregate Fair Value Of Indemnified Securities On Loan AggregateFairValueOfIndemnifiedSecuritiesOnLoan	367901000000	USD
CY2020Q4	stt	Stand By Letters Of Credit StandByLettersOfCredit	3330000000	USD
CY2019Q4	stt	Stand By Letters Of Credit StandByLettersOfCredit	3324000000	USD
CY2020	stt	Unfunded Commitments To Extend Credit Short Term UnfundedCommitmentsToExtendCreditShortTerm	0.73
CY2020	stt	Unfunded Commitmentto Extend Credit Term UnfundedCommitmenttoExtendCreditTerm	P1Y
CY2020	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The following table summarizes the aggregate fair values of indemnified securities financing and related collateral, as well as collateral invested in indemnified repurchase agreements, as of the dates indicated:</span></div><div style="margin-bottom:5pt;margin-top:8pt;text-align:justify"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:100.000%"><tr><td style="width:1.0%"/><td style="width:47.642%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:23.742%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:1.372%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:23.744%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">(In millions)</span></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">December 31, 2020</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">December 31, 2019</span></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:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">Fair value of indemnified securities financing</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:'Arial',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">440,875</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">$</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:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">367,901 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">Fair value of cash and securities held by us, as agent, as collateral for indemnified securities financing</span></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">463,273</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%"> </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">385,428 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">Fair value of collateral for indemnified securities financing invested in indemnified 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:'Arial',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">54,432</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;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 colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">45,658 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">Fair value of cash and securities held by us or our agents as collateral for investments in indemnified repurchase agreements</span></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">58,092</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%"> </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:7.5pt;font-weight:400;line-height:100%">48,887 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div>
CY2020Q4	stt	Aggregate Fair Value Of Indemnified Securities On Loan AggregateFairValueOfIndemnifiedSecuritiesOnLoan	440875000000	USD
CY2019Q4	stt	Aggregate Fair Value Of Indemnified Securities On Loan AggregateFairValueOfIndemnifiedSecuritiesOnLoan	367901000000	USD
CY2020Q4	stt	Aggregate Fair Value Of Cash And Securities Held As Collateral For Indemnified Securities AggregateFairValueOfCashAndSecuritiesHeldAsCollateralForIndemnifiedSecurities	463273000000	USD
CY2019Q4	stt	Aggregate Fair Value Of Cash And Securities Held As Collateral For Indemnified Securities AggregateFairValueOfCashAndSecuritiesHeldAsCollateralForIndemnifiedSecurities	385428000000	USD
CY2020Q4	stt	Collateralfor Indemnified Securities Investedin Indemnified Repurchase Agreements CollateralforIndemnifiedSecuritiesInvestedinIndemnifiedRepurchaseAgreements	54432000000	USD
CY2019Q4	stt	Collateralfor Indemnified Securities Investedin Indemnified Repurchase Agreements CollateralforIndemnifiedSecuritiesInvestedinIndemnifiedRepurchaseAgreements	45658000000	USD
CY2020Q4	stt	Aggregate Fair Value Of Cash And Securities Held As Collateral For Indemnified Repurchase Agreements AggregateFairValueOfCashAndSecuritiesHeldAsCollateralForIndemnifiedRepurchaseAgreements	58092000000	USD
CY2019Q4	stt	Aggregate Fair Value Of Cash And Securities Held As Collateral For Indemnified Repurchase Agreements AggregateFairValueOfCashAndSecuritiesHeldAsCollateralForIndemnifiedRepurchaseAgreements	48887000000	USD
CY2020Q4	us-gaap	Cash Collateral For Borrowed Securities CashCollateralForBorrowedSecurities	18330000000	USD
CY2019Q4	us-gaap	Cash Collateral For Borrowed Securities CashCollateralForBorrowedSecurities	18520000000	USD
CY2020	us-gaap	Loss Contingency Disclosures LossContingencyDisclosures	Contingencies<div style="margin-top:3pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Legal and Regulatory Matters</span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In the ordinary course of business, we and our subsidiaries are involved in disputes, litigation, and governmental or regulatory inquiries and investigations, both pending and threatened. These matters, if resolved adversely against us or settled, may result in monetary awards or payments, fines and penalties or require changes in our business practices. The resolution or settlement of these matters is inherently difficult to predict. Based on our assessment of these pending matters, we do not believe that the amount of any judgment, settlement or other action arising from any pending matter is likely to have a material adverse effect on our consolidated financial condition. However, an adverse outcome or development in certain of the matters described below could have a material adverse effect on our consolidated results of operations for the period in which such matter is resolved, or an accrual is determined to be required, on our consolidated financial condition, or on our reputation. </span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">We evaluate our needs for accruals of loss contingencies related to legal and regulatory proceedings on a case-by-case basis. When we have a liability that we deem probable, and we deem the amount of such liability can be reasonably estimated as of the date of our consolidated financial statements, we accrue our estimate of the amount of loss. We also consider a loss probable and establish an accrual when we make, or intend to make, an offer of settlement. Once established, an accrual is subject to subsequent adjustment as a result of additional information. The resolution of legal and regulatory proceedings and the amount of reasonably estimable loss (or range thereof) are inherently difficult to predict, especially in the early stages of proceedings. Even if a loss is probable, an amount (or range) of loss might not be reasonably estimated until the later stages of the proceeding due to many factors such as the presence of complex or novel legal theories, the discretion of governmental authorities in seeking sanctions or negotiating resolutions in civil and criminal matters, the pace and timing of discovery and other assessments of facts and the procedural posture of the matter (collectively, "factors influencing reasonable estimates"). </span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">As of December 31, 2020, our aggregate accruals for loss contingencies for legal, regulatory and related matters totaled approximately $144 million, including potential fines by government agencies and civil litigation with respect to the matters specifically discussed below. To the extent that we have established accruals in our consolidated statement of condition for probable loss contingencies, such accruals may not be sufficient to </span></div><div style="margin-top:3pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">cover our ultimate financial exposure associated with any settlements or judgments. Any such ultimate financial exposure, or proceedings to which we may become subject in the future, could have a material adverse effect on our businesses, on our future consolidated financial statements or on our reputation. </span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">As of December 31, 2020, for those matters for which we have accrued probable loss contingencies (including the Invoicing Matter described below) and for other matters for which loss is reasonably possible (but not probable) in future periods, and for which we are able to estimate a range of reasonably possible loss, our estimate of the aggregate reasonably possible loss (in excess of any accrued amounts) ranges up to approximately $40 million. Our estimate with respect to the aggregate 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, which may change quickly and significantly from time to time, particularly if and as we engage with applicable governmental agencies or plaintiffs in connection with a proceeding. Also, the matters underlying the reasonably possible loss will change from time to time. As a result, actual results may vary significantly from the current estimate.</span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In certain pending matters, it is not currently feasible to reasonably estimate the amount or a range of reasonably possible loss, and such losses, which may be significant, are not included in the estimate of reasonably possible loss discussed above. This is due to, among other factors, the factors influencing reasonable estimates described above. An adverse outcome in one or more of the matters for which we have not estimated the amount or a range of reasonably possible loss, individually or in the aggregate, could have a material adverse effect on our businesses, on our future consolidated financial statements or on our reputation. Given that our actual losses from any legal or regulatory proceeding for which we have provided an estimate of the reasonably possible loss could significantly exceed such estimate, and given that we cannot estimate reasonably possible loss for all legal and regulatory proceedings as to which we may be subject now or in the future, no conclusion as to our ultimate exposure from current pending or potential legal or regulatory proceedings should be drawn from the current estimate of reasonably possible loss. </span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The following discussion provides information with respect to significant legal, governmental and regulatory matters. </span></div><div style="margin-top:3pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Invoicing Matter</span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In 2015, we determined that we had incorrectly invoiced clients for certain expenses. We have </span></div><div style="display:inline-block;vertical-align:top;width:46.491%"><div style="margin-top:3pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">reimbursed most of our affected customers for those expenses, and we have implemented enhancements to our billing processes. In connection with our enhancements to our billing processes, we continue to review historical billing practices and may from time to time identify additional remediation. In 2017, we identified an additional area of incorrect expense billing associated with mailing services in our retirement services business. We currently expect the cumulative total of our payments to customers for these invoicing errors, including the error in the retirement services business, to be at least $370 million, all of which has been paid or is accrued. However, we may identify additional remediation costs.</span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In March 2017, a purported class action was commenced against us alleging that our invoicing practices violated duties owed to retirement plan customers under the Employee Retirement Income Security Act. In addition, we have received a purported class action demand letter alleging that our invoicing practices were unfair and deceptive under Massachusetts law. A class of customers, or particular customers, may assert that we have not paid to them all amounts incorrectly invoiced, and may seek double or treble damages under Massachusetts law. </span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">We are also cooperating with investigations by governmental and regulatory authorities on these matters, including the civil and criminal divisions of the DOJ and the DOL, which reviews could result in significant fines or other sanctions, civil and criminal, against us. In June 2019, we reached an agreement with the SEC to settle its claims that we violated the recordkeeping provisions of Section 34(b) of the Investment Company Act of 1940 and caused violations of Section 31(a) of the Investment Company Act and Rules 31a-1(a) and 31a-1(b) thereunder in connection with our overcharges of customers which are registered investment companies. In reaching this settlement, we neither admitted nor denied the claims contained in the SEC’s order, and agreed to pay a civil monetary penalty of $40 million. Also in June 2019, we reached an agreement with the Massachusetts Attorney General’s office to resolve its claims related to this matter. In reaching this settlement, we neither admitted nor denied the claims in the order, and agreed to pay a civil monetary penalty of $5.5 million. The costs associated with these settlements were within our related previously established accruals for loss contingencies. The SEC and Massachusetts Attorney General’s office settlements both recognize that the payment of $48.8 million in disgorgement and interest is satisfied by our direct reimbursements of our customers. </span></div></div><div style="display:inline-block;max-width:7.017%;min-width:6.017%;vertical-align:top"/><div style="display:inline-block;vertical-align:top;width:46.492%"><div style="margin-bottom:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In January 2020, the DOJ outlined a framework for a possible resolution of their review. We are discussing the terms of a potential settlement of this matter with the DOJ. Separately, we have inquired of the DOL as to the status of their review but have not entered into settlement discussions with the DOL. There can be no assurance that any settlement with the DOJ or DOL will be reached on financial or other terms acceptable to us or at all. The aggregate amount of penalties that may potentially be imposed upon us in connection with the resolution of all outstanding investigations into our historical billing practices is not currently known. We have established a legal accrual with respect to the pending governmental investigations and civil litigation with respect to this matter, however, our ultimate liability with respect to this matter might be significantly in excess of our current accrual. Government authorities have significant discretion in criminal and civil matters as to the fines and other penalties they may seek to impose. Any resolution of the DOJ and DOL claims may involve penalties that could be a significant percentage, or a multiple of, all or a portion of the overcharge. The severity of such fines or penalties could take into account factors such as the amount or duration of our incorrect invoicing and the government’s or regulators’ assessment of the conduct of our employees, as well as prior conduct such as that which resulted in our January 2017 deferred prosecution agreement and settlement of civil claims regarding our indirect FX business. </span></div><div style="margin-bottom:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The outcome of any of these proceedings and, in particular, any criminal sanction could materially adversely affect our results of operations and could have significant additional consequences for our business and reputation. </span></div><div style="margin-top:4.5pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Federal Reserve/Massachusetts Division of Banks Written Agreement</span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On June 1, 2015, we entered into a written agreement with the Federal Reserve and the Massachusetts Division of Banks relating to deficiencies identified in our compliance programs with the requirements of the Bank Secrecy Act, Anti-Money Laundering regulations and U.S. economic sanctions regulations promulgated by the Office of Foreign Assets Control. As part of this enforcement action, we have been required to, among other things, implement improvements to our compliance programs. In June 2020, the Federal Reserve and the Massachusetts Division of Banks terminated the written agreement, based on our compliance with its requirements.</span></div><div style="margin-top:3pt;text-align:justify"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Shareholder Litigation</span></div><div style="text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">A shareholder of ours has filed a derivative complaint against the Company’s past and present officers and directors to recover alleged losses </span></div></div>incurred by the Company relating to the invoicing matter and to the Ohio public retirement plans matter.<div style="margin-top:3pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Income Taxes</span></div><div style="margin-top:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In determining our provision for income taxes, we make certain judgments and interpretations with respect to tax laws in jurisdictions in which we have business operations. Because of the complex nature of these laws, in the normal course of our business, we are subject to challenges from U.S. and non-U.S. income tax authorities regarding the amount of income taxes due. These challenges may result in adjustments to the timing or amount of taxable income or deductions or the allocation of taxable income among tax jurisdictions. We recognize a tax benefit when it is more likely than not that our position will result in a tax deduction or credit. Unrecognized tax benefits of approximately $308 million as of December 31, 2020 increased from $149 million as of December 31, 2019. </span></div><div style="text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:115%">We are presently under audit by a number of tax authorities, and the Internal Revenue Service is currently reviewing our U.S. income tax returns, including amended returns, for tax years 2014-2018. The earliest tax year open to examination in jurisdictions where we have material operations is 2013. Management believes that we have sufficiently accrued liabilities as of December 31, 2020 for potential tax exposures.</span></div>
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CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	0	USD
CY2020Q4	stt	Lease Liability Payments Due Year Five LeaseLiabilityPaymentsDueYearFive	93000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	275000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	0	USD
CY2020Q4	stt	Lease Liability Payments Due After Year Five LeaseLiabilityPaymentsDueAfterYearFive	275000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	980000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	113000000	USD
CY2020Q4	stt	Lease Liability Payments Due LeaseLiabilityPaymentsDue	1093000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	89000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	10000000	USD
CY2020Q4	stt	Lease Liability Undiscounted Excess Amount LeaseLiabilityUndiscountedExcessAmount	99000000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	891000000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	103000000	USD
CY2020Q4	stt	Lease Liability LeaseLiability	994000000	USD
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P2Y8M12D
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P3Y9M18D
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y1M6D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y7M6D
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.07
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.07
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.03
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.03
CY2020	stt	Donations Expense DonationsExpense	20000000	USD
CY2020	us-gaap	Professional Fees ProfessionalFees	364000000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	321000000	USD
CY2018	us-gaap	Professional Fees ProfessionalFees	357000000	USD
CY2020	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	77000000	USD
CY2019	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	114000000	USD
CY2018	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	115000000	USD
CY2020	stt	Regulatory Feesand Assessments RegulatoryFeesandAssessments	61000000	USD
CY2019	stt	Regulatory Feesand Assessments RegulatoryFeesandAssessments	73000000	USD
CY2018	stt	Regulatory Feesand Assessments RegulatoryFeesandAssessments	91000000	USD
CY2020	stt	Securities Processing Expense SecuritiesProcessingExpense	41000000	USD
CY2019	stt	Securities Processing Expense SecuritiesProcessingExpense	75000000	USD
CY2018	stt	Securities Processing Expense SecuritiesProcessingExpense	52000000	USD
CY2019	stt	Donations Expense DonationsExpense	51000000	USD
CY2018	stt	Donations Expense DonationsExpense	12000000	USD
CY2020	stt	Bank Operations Expense BankOperationsExpense	18000000	USD
CY2019	stt	Bank Operations Expense BankOperationsExpense	43000000	USD
CY2018	stt	Bank Operations Expense BankOperationsExpense	70000000	USD
CY2020	us-gaap	General Insurance Expense GeneralInsuranceExpense	14000000	USD
CY2019	us-gaap	General Insurance Expense GeneralInsuranceExpense	19000000	USD
CY2018	us-gaap	General Insurance Expense GeneralInsuranceExpense	18000000	USD
CY2020	us-gaap	Other General Expense OtherGeneralExpense	370000000	USD
CY2019	us-gaap	Other General Expense OtherGeneralExpense	566000000	USD
CY2018	us-gaap	Other General Expense OtherGeneralExpense	461000000	USD
CY2020	us-gaap	Other Expenses OtherExpenses	965000000	USD
CY2019	us-gaap	Other Expenses OtherExpenses	1262000000	USD
CY2018	us-gaap	Other Expenses OtherExpenses	1176000000	USD
CY2020	us-gaap	Restructuring Charges RestructuringCharges	133000000	USD
CY2020	stt	Reduction Of Real Estate Footprint ReductionOfRealEstateFootprint	0.13
CY2019	us-gaap	Restructuring Charges RestructuringCharges	110000000	USD
CY2017Q4	us-gaap	Restructuring Reserve RestructuringReserve	201000000	USD
CY2018	us-gaap	Restructuring Charges RestructuringCharges	300000000	USD
CY2018	us-gaap	Payments For Restructuring PaymentsForRestructuring	153000000	USD
CY2018Q4	us-gaap	Restructuring Reserve RestructuringReserve	341000000	USD
CY2019	us-gaap	Restructuring Charges RestructuringCharges	110000000	USD
CY2019	us-gaap	Payments For Restructuring PaymentsForRestructuring	251000000	USD
CY2019Q4	us-gaap	Restructuring Reserve RestructuringReserve	198000000	USD
CY2020	us-gaap	Restructuring Charges RestructuringCharges	133000000	USD
CY2020	us-gaap	Payments For Restructuring PaymentsForRestructuring	131000000	USD
CY2020Q4	us-gaap	Restructuring Reserve RestructuringReserve	196000000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	241000000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	157000000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	122000000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	122000000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	86000000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	148000000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	310000000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	357000000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	374000000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	673000000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	600000000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	644000000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-168000000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-6000000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-128000000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	5000000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	33000000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-22000000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-31000000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-157000000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	14000000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-194000000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-130000000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-136000000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	479000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	470000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	508000000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.038
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.034
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.031
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.013
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.015
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.020
CY2018	stt	Effective Income Tax Rate Reconciliation Nondeductible Litigation Expense Percent EffectiveIncomeTaxRateReconciliationNondeductibleLitigationExpensePercent	0.003
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.002
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.051
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.054
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.041
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.008
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.001
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Foreign Income Tax Rate Differential EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential	0.006
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Restructuring Charges EffectiveIncomeTaxRateReconciliationNondeductibleExpenseRestructuringCharges	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Restructuring Charges EffectiveIncomeTaxRateReconciliationNondeductibleExpenseRestructuringCharges	-0.043
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Restructuring Charges EffectiveIncomeTaxRateReconciliationNondeductibleExpenseRestructuringCharges	0
CY2020	stt	Effective Income Tax Rate Reconciliation Tax Credit Foreign Limitations Percent EffectiveIncomeTaxRateReconciliationTaxCreditForeignLimitationsPercent	0.009
CY2019	stt	Effective Income Tax Rate Reconciliation Tax Credit Foreign Limitations Percent EffectiveIncomeTaxRateReconciliationTaxCreditForeignLimitationsPercent	-0.022
CY2018	stt	Effective Income Tax Rate Reconciliation Tax Credit Foreign Limitations Percent EffectiveIncomeTaxRateReconciliationTaxCreditForeignLimitationsPercent	-0.002
CY2020	stt	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Actof2017 Deferred Tax Asset Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017DeferredTaxAssetPercent	0
CY2019	stt	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Actof2017 Deferred Tax Asset Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017DeferredTaxAssetPercent	0
CY2018	stt	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Actof2017 Deferred Tax Asset Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017DeferredTaxAssetPercent	-0.010
CY2020	stt	Effective Income Tax Rate Reconciliation Nondeductible Litigation Expense Percent EffectiveIncomeTaxRateReconciliationNondeductibleLitigationExpensePercent	0
CY2019	stt	Effective Income Tax Rate Reconciliation Nondeductible Litigation Expense Percent EffectiveIncomeTaxRateReconciliationNondeductibleLitigationExpensePercent	0.016
CY2018	stt	Effective Income Tax Rate Reconciliation Gilti Percent EffectiveIncomeTaxRateReconciliationGILTIPercent	0.002
CY2020Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	5800000000	USD
CY2020Q4	stt	Deferred Tax Assets Other Amortizable Assets DeferredTaxAssetsOtherAmortizableAssets	385000000	USD
CY2019Q4	stt	Deferred Tax Assets Other Amortizable Assets DeferredTaxAssetsOtherAmortizableAssets	394000000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.004
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.006
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.165
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.173
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.163
CY2018	us-gaap	Tax Cuts And Jobs Act Of2017 Change In Tax Rate Income Tax Expense Benefit TaxCutsAndJobsActOf2017ChangeInTaxRateIncomeTaxExpenseBenefit	-32000000	USD
CY2020	stt	Effective Income Tax Rate Reconciliation Gilti Percent EffectiveIncomeTaxRateReconciliationGILTIPercent	0.002
CY2019	stt	Effective Income Tax Rate Reconciliation Gilti Percent EffectiveIncomeTaxRateReconciliationGILTIPercent	0.003
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	564000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	387000000	USD
CY2020Q4	stt	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Lease Liability DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLeaseLiability	243000000	USD
CY2019Q4	stt	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Lease Liability DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLeaseLiability	254000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	110000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	120000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Restructuring Charges DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsRestructuringCharges	129000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Restructuring Charges DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsRestructuringCharges	104000000	USD
CY2020Q4	stt	Deferred Tax Assets Operating Lossand Other Carryforwards DeferredTaxAssetsOperatingLossandOtherCarryforwards	101000000	USD
CY2019Q4	stt	Deferred Tax Assets Operating Lossand Other Carryforwards DeferredTaxAssetsOperatingLossandOtherCarryforwards	73000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	56000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Pensions DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions	66000000	USD
CY2020Q4	stt	Deferred Tax Assets Foreign Currency Translation DeferredTaxAssetsForeignCurrencyTranslation	3000000	USD
CY2019Q4	stt	Deferred Tax Assets Foreign Currency Translation DeferredTaxAssetsForeignCurrencyTranslation	57000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1591000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1455000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	295000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	330000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1296000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1125000000	USD
CY2020Q4	stt	Deferred Tax Liabilities Fixed And Intangible Assets DeferredTaxLiabilitiesFixedAndIntangibleAssets	765000000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1362000000	USD
CY2019Q4	stt	Deferred Tax Liabilities Fixed And Intangible Assets DeferredTaxLiabilitiesFixedAndIntangibleAssets	763000000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	269000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	258000000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	187000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	223000000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	321000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	86000000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	51000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	32000000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1593000000	USD
CY2020Q4	stt	Deferred Tax Assets Other Amortizable Assets DeferredTaxAssetsOtherAmortizableAssets	385000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards General Business DeferredTaxAssetsTaxCreditCarryforwardsGeneralBusiness	564000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	65000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other Loss Carryforwards DeferredTaxAssetsOtherLossCarryforwards	19000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	17000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	308000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	149000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	108000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	294000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	140000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	100000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	149000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	108000000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	94000000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	17000000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	40000000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	47000000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	13000000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	12000000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	137000000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	49000000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	44000000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	25000000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	4000000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	2000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	308000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	149000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	108000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	308000000	USD
CY2020Q4	us-gaap	Decrease In Unrecognized Tax Benefits Is Reasonably Possible DecreaseInUnrecognizedTaxBenefitsIsReasonablyPossible	104000000	USD
CY2020	us-gaap	Income Tax Examination Interest Expense IncomeTaxExaminationInterestExpense	6000000	USD
CY2019	us-gaap	Income Tax Examination Interest Expense IncomeTaxExaminationInterestExpense	5000000	USD
CY2018	us-gaap	Income Tax Examination Interest Expense IncomeTaxExaminationInterestExpense	1000000	USD
CY2019	us-gaap	Dividends Preferred Stock DividendsPreferredStock	232000000	USD
CY2018	us-gaap	Dividends Preferred Stock DividendsPreferredStock	188000000	USD
CY2020	stt	Dividends And Undistributed Earnings Allocated To Participating Securities DividendsAndUndistributedEarningsAllocatedToParticipatingSecurities	1000000	USD
CY2020Q4	us-gaap	Income Tax Examination Interest Accrued IncomeTaxExaminationInterestAccrued	14000000	USD
CY2019Q4	us-gaap	Income Tax Examination Interest Accrued IncomeTaxExaminationInterestAccrued	10000000	USD
CY2018Q4	us-gaap	Income Tax Examination Interest Accrued IncomeTaxExaminationInterestAccrued	8000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	2420000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	2242000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	2593000000	USD
CY2020	us-gaap	Dividends Preferred Stock DividendsPreferredStock	162000000	USD
CY2019	stt	Dividends And Undistributed Earnings Allocated To Participating Securities DividendsAndUndistributedEarningsAllocatedToParticipatingSecurities	1000000	USD
CY2018	stt	Dividends And Undistributed Earnings Allocated To Participating Securities DividendsAndUndistributedEarningsAllocatedToParticipatingSecurities	1000000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	2257000000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	2009000000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	2404000000	USD
CY2018	stt	Fees And Commissions Securities Finance FeesAndCommissionsSecuritiesFinance	543000000	USD
CY2020	stt	Fees And Commissions Processing Fees And Other FeesAndCommissionsProcessingFeesAndOther	733000000	USD
CY2019	stt	Fees And Commissions Processing Fees And Other FeesAndCommissionsProcessingFeesAndOther	720000000	USD
CY2018	stt	Fees And Commissions Processing Fees And Other FeesAndCommissionsProcessingFeesAndOther	438000000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	352865000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	369911000	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.43
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	371983000	shares
CY2020	stt	Stock Options And Stock Awards StockOptionsAndStockAwards	4241000	shares
CY2019	stt	Stock Options And Stock Awards StockOptionsAndStockAwards	3755000	shares
CY2018	stt	Stock Options And Stock Awards StockOptionsAndStockAwards	4493000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	357106000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	373666000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	376476000	shares
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1066000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2052000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1011000	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.40
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.46
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.32
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.38
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.39
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020	stt	Fees And Commissions Servicing Fees FeesAndCommissionsServicingFees	5167000000	USD
CY2019	stt	Fees And Commissions Servicing Fees FeesAndCommissionsServicingFees	5074000000	USD
CY2018	stt	Fees And Commissions Servicing Fees FeesAndCommissionsServicingFees	5421000000	USD
CY2020	stt	Fees And Commissions Management Fees FeesAndCommissionsManagementFees	1880000000	USD
CY2019	stt	Fees And Commissions Management Fees FeesAndCommissionsManagementFees	1824000000	USD
CY2018	stt	Fees And Commissions Management Fees FeesAndCommissionsManagementFees	1899000000	USD
CY2020	stt	Fees And Commissions Foreign Exchange Trading Services FeesAndCommissionsForeignExchangeTradingServices	1363000000	USD
CY2019	stt	Fees And Commissions Foreign Exchange Trading Services FeesAndCommissionsForeignExchangeTradingServices	1058000000	USD
CY2018	stt	Fees And Commissions Foreign Exchange Trading Services FeesAndCommissionsForeignExchangeTradingServices	1153000000	USD
CY2020	stt	Fees And Commissions Securities Finance FeesAndCommissionsSecuritiesFinance	356000000	USD
CY2019	stt	Fees And Commissions Securities Finance FeesAndCommissionsSecuritiesFinance	471000000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	9499000000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	9147000000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	9454000000	USD
CY2020	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	2200000000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	2566000000	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	2671000000	USD
CY2020	us-gaap	Other Operating Income OtherOperatingIncome	4000000	USD
CY2019	us-gaap	Other Operating Income OtherOperatingIncome	43000000	USD
CY2018	us-gaap	Other Operating Income OtherOperatingIncome	6000000	USD
CY2020	us-gaap	Revenues Revenues	11703000000	USD
CY2019	us-gaap	Revenues Revenues	11756000000	USD
CY2018	us-gaap	Revenues Revenues	12131000000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	88000000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	10000000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	15000000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	8716000000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	9034000000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	9015000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2899000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2712000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	3101000000	USD
CY2020	stt	Pre Tax Margin PreTaxMargin	0.25
CY2019	stt	Pre Tax Margin PreTaxMargin	0.23
CY2018	stt	Pre Tax Margin PreTaxMargin	0.26
CY2020	stt	Total Average Assets TotalAverageAssets	269300000000	USD
CY2019	stt	Total Average Assets TotalAverageAssets	223300000000	USD
CY2018	stt	Total Average Assets TotalAverageAssets	223400000000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	line_of_business
CY2020	stt	Fees And Commissions Servicing Fees FeesAndCommissionsServicingFees	5167000000	USD
CY2020	stt	Fees And Commissions Management Fees FeesAndCommissionsManagementFees	1880000000	USD
CY2020	stt	Fees And Commissions Foreign Exchange Trading Services FeesAndCommissionsForeignExchangeTradingServices	1363000000	USD
CY2019	stt	Fees And Commissions Management Fees FeesAndCommissionsManagementFees	1824000000	USD
CY2019	stt	Fees And Commissions Foreign Exchange Trading Services FeesAndCommissionsForeignExchangeTradingServices	1058000000	USD
CY2019	stt	Fees And Commissions Securities Finance FeesAndCommissionsSecuritiesFinance	471000000	USD
CY2019	stt	Fees And Commissions Processing Fees And Other FeesAndCommissionsProcessingFeesAndOther	720000000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	9147000000	USD
CY2019	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	2566000000	USD
CY2020	stt	Fees And Commissions Securities Finance FeesAndCommissionsSecuritiesFinance	356000000	USD
CY2020	stt	Fees And Commissions Processing Fees And Other FeesAndCommissionsProcessingFeesAndOther	733000000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	9499000000	USD
CY2020	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	2200000000	USD
CY2020	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	4000000	USD
CY2020	us-gaap	Revenues Revenues	11703000000	USD
CY2019	stt	Fees And Commissions Servicing Fees FeesAndCommissionsServicingFees	5074000000	USD
CY2019	us-gaap	Other Operating Income OtherOperatingIncome	43000000	USD
CY2019	us-gaap	Revenues Revenues	11756000000	USD
CY2018	stt	Fees And Commissions Servicing Fees FeesAndCommissionsServicingFees	5421000000	USD
CY2018	us-gaap	Revenues Revenues	12131000000	USD
CY2018	stt	Fees And Commissions Management Fees FeesAndCommissionsManagementFees	1899000000	USD
CY2018	stt	Fees And Commissions Foreign Exchange Trading Services FeesAndCommissionsForeignExchangeTradingServices	1153000000	USD
CY2018	stt	Fees And Commissions Securities Finance FeesAndCommissionsSecuritiesFinance	543000000	USD
CY2018	stt	Fees And Commissions Processing Fees And Other FeesAndCommissionsProcessingFeesAndOther	438000000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	9454000000	USD
CY2018	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	2671000000	USD
CY2018	us-gaap	Other Operating Income OtherOperatingIncome	6000000	USD
CY2018	us-gaap	Revenues Revenues	12131000000	USD
CY2020	us-gaap	Revenues Revenues	11703000000	USD
CY2019	us-gaap	Revenues Revenues	11756000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2899000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2712000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	3101000000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21

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$STT
STATE STREET CORP Stock $stt

2019 Q4 Form 10-K Financial Statement

#000009375121000476 Filed on February 19, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$STT STATE STREET CORP Stock $stt

2019 Q4 Form 10-K Financial Statement

#000009375121000476 Filed on February 19, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$STT
STATE STREET CORP Stock $stt