$CMA
COMERICA INC /NEW/ Stock $cma

$cma Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-Q Financial Statement

#000002841220000105 Filed on October 30, 2020

Income Statement

Concept	2020 Q4	2020 Q3	2019 Q3
Revenue	$489.0M	$484.0M	$711.0M
YoY Change	-25.8%	-31.93%	5.33%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$26.00M	$27.00M	$27.00M
YoY Change	-13.33%	0.0%	-10.0%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$20.00M	$26.00M	$125.0M
YoY Change	-82.61%	-79.2%	64.47%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$286.0M	$267.0M	$372.0M
YoY Change	-18.52%	-28.23%	-2.36%
Income Tax	$65.00M	$50.00M	$80.00M
% Of Pretax Income	22.73%	18.73%	21.51%
Net Earnings	$221.0M	$217.0M	$292.0M
YoY Change	-17.84%	-25.68%	-8.18%
Net Earnings / Revenue	45.19%	44.83%	41.07%
Basic Earnings Per Share	$1.54	$1.49	$1.98
Diluted Earnings Per Share	$1.53	$1.48	$1.96
COMMON SHARES
Basic Shares Outstanding	139.1M shares	139.0M shares	147.0M shares
Diluted Shares Outstanding		140.0M shares	148.0M shares

Balance Sheet

Concept	2020 Q4	2020 Q3	2019 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$15.77B	$11.14B	$4.117B
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	$459.0M	$456.0M	$467.0M
YoY Change	0.44%	-2.36%	-1.06%
Goodwill	$635.0M
YoY Change	0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$88.13B	$83.63B	$72.85B
YoY Change	20.06%	14.8%	1.96%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$1.482B	$1.534B	$1.477B
YoY Change	2.92%	3.86%	27.99%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$10.00M	$51.00M
YoY Change	-100.0%	-80.39%	-39.29%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$1.482B	$1.534B	$1.477B
YoY Change	2.92%	3.86%	27.99%
LONG-TERM LIABILITIES
Long-Term Debt	$2.928B	$2.954B	$3.511B
YoY Change	-15.6%	-15.86%	34.11%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$2.928B	$2.954B	$3.511B
YoY Change	-15.6%	-15.86%	34.11%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.482B	$1.534B	$1.477B
Total Long-Term Liabilities	$2.928B	$2.954B	$3.511B
Total Liabilities	$80.08B	$75.76B	$65.65B
YoY Change	21.19%	15.4%	3.12%
SHAREHOLDERS EQUITY
Retained Earnings	$9.727B	$9.511B	$9.369B
YoY Change	1.98%	1.52%	9.11%
Common Stock	$3.326B	$3.320B	$3.313B
YoY Change	0.33%	0.21%	0.85%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$5.461B	$5.467B	$5.146B
YoY Change	3.21%	6.24%	48.09%
Treasury Stock Shares	89.00M shares	89.10M shares	84.03M shares
Shareholders Equity	$8.050B	$7.874B	$7.200B
YoY Change
Total Liabilities & Shareholders Equity	$88.13B	$83.63B	$72.85B
YoY Change	20.06%	14.8%	1.96%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2019 Q3
OPERATING ACTIVITIES
Net Income	$221.0M	$217.0M	$292.0M
YoY Change	-17.84%	-25.68%	-8.18%
Depreciation, Depletion And Amortization	$26.00M	$27.00M	$27.00M
YoY Change	-13.33%	0.0%	-10.0%
Cash From Operating Activities	$208.0M	-$24.00M	$444.0M
YoY Change	-5.88%	-105.41%	25.78%
INVESTING ACTIVITIES
Capital Expenditures	-$28.00M	-$22.00M	-$33.00M
YoY Change	16.67%	-33.33%	37.5%
Acquisitions
YoY Change
Other Investing Activities	$56.00M	-$1.264B	$264.0M
YoY Change	-95.0%	-578.79%	-65.58%
Cash From Investing Activities	$28.00M	-$1.286B	$231.0M
YoY Change	-97.45%	-656.71%	-68.91%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	4.390B	-860.0M	-139.0M
YoY Change	1043.23%	518.71%	-84.84%
NET CHANGE
Cash From Operating Activities	208.0M	-24.00M	444.0M
Cash From Investing Activities	28.00M	-1.286B	231.0M
Cash From Financing Activities	4.390B	-860.0M	-139.0M
Net Change In Cash	4.626B	-2.170B	536.0M
YoY Change	171.96%	-504.85%	199.44%
FREE CASH FLOW
Cash From Operating Activities	$208.0M	-$24.00M	$444.0M
Capital Expenditures	-$28.00M	-$22.00M	-$33.00M
Free Cash Flow	$236.0M	-$2.000M	$477.0M
YoY Change	-3.67%	-100.42%	26.53%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Entity Central Index Key EntityCentralIndexKey	0000028412
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Amendment Flag AmendmentFlag	false
CY2019Q4	cma	Increaseinthe Cet1capitalratio IncreaseintheCET1capitalratio	0.0002
	us-gaap	Average Term Of Credit Risk Derivatives1 AverageTermOfCreditRiskDerivatives1	P4Y6M
CY2019Q4	cma	Fair Value Amount Of Derivative Credit Risk Participation Agreements FairValueAmountOfDerivativeCreditRiskParticipationAgreements	0	USD
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2020-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	1-10706
	dei	Entity Registrant Name EntityRegistrantName	Comerica Incorporated
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	38-1998421
	dei	Entity Address Address Line1 EntityAddressAddressLine1	1717 Main Street, MC 6404
	dei	Entity Address City Or Town EntityAddressCityOrTown	Dallas
	dei	Entity Address State Or Province EntityAddressStateOrProvince	TX
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	75201
	dei	City Area Code CityAreaCode	(214)
	dei	Local Phone Number LocalPhoneNumber	462-6831
	dei	Security12b Title Security12bTitle	Common Stock, $5 par value
	dei	Trading Symbol TradingSymbol	CMA
	dei	Security Exchange Name SecurityExchangeName	NYSE
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
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	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	-8000000	USD
CY2020Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	29000000	USD
CY2019Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	23000000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	84000000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	70000000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	252000000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	256000000	USD
	us-gaap	Noninterest Income NoninterestIncome	736000000	USD
	us-gaap	Noninterest Income NoninterestIncome	744000000	USD
CY2020Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	257000000	USD
CY2019Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	253000000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	748000000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	763000000	USD
CY2020Q3	cma	Outside Processing Fee Expense OutsideProcessingFeeExpense	58000000	USD
CY2019Q3	cma	Outside Processing Fee Expense OutsideProcessingFeeExpense	66000000	USD
	cma	Outside Processing Fee Expense OutsideProcessingFeeExpense	177000000	USD
	cma	Outside Processing Fee Expense OutsideProcessingFeeExpense	194000000	USD
CY2020Q3	us-gaap	Occupancy Net OccupancyNet	40000000	USD
CY2019Q3	us-gaap	Occupancy Net OccupancyNet	39000000	USD
	us-gaap	Occupancy Net OccupancyNet	114000000	USD
	us-gaap	Occupancy Net OccupancyNet	113000000	USD
CY2020Q3	cma	Software Expenses SoftwareExpenses	39000000	USD
CY2019Q3	cma	Software Expenses SoftwareExpenses	30000000	USD
	cma	Software Expenses SoftwareExpenses	115000000	USD
	cma	Software Expenses SoftwareExpenses	87000000	USD
CY2020Q3	us-gaap	Equipment Expense EquipmentExpense	12000000	USD
CY2019Q3	us-gaap	Equipment Expense EquipmentExpense	13000000	USD
	us-gaap	Equipment Expense EquipmentExpense	36000000	USD
	us-gaap	Equipment Expense EquipmentExpense	37000000	USD
CY2020Q3	us-gaap	Advertising Expense AdvertisingExpense	9000000	USD
CY2019Q3	us-gaap	Advertising Expense AdvertisingExpense	10000000	USD
	us-gaap	Advertising Expense AdvertisingExpense	24000000	USD
	us-gaap	Advertising Expense AdvertisingExpense	24000000	USD
CY2020Q3	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	8000000	USD
CY2019Q3	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	6000000	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	24000000	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	17000000	USD
CY2020Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	23000000	USD
CY2019Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	18000000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	73000000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	57000000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	446000000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	435000000	USD
	us-gaap	Noninterest Expense NoninterestExpense	1311000000	USD
	us-gaap	Noninterest Expense NoninterestExpense	1292000000	USD
CY2020Q3	cma	Income Loss From Continuing Operations Before Income Taxes IncomeLossFromContinuingOperationsBeforeIncomeTaxes	259000000	USD
CY2019Q3	cma	Income Loss From Continuing Operations Before Income Taxes IncomeLossFromContinuingOperationsBeforeIncomeTaxes	372000000	USD
	cma	Income Loss From Continuing Operations Before Income Taxes IncomeLossFromContinuingOperationsBeforeIncomeTaxes	313000000	USD
	cma	Income Loss From Continuing Operations Before Income Taxes IncomeLossFromContinuingOperationsBeforeIncomeTaxes	1181000000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	48000000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	80000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	54000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	252000000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	211000000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	292000000	USD
	us-gaap	Profit Loss ProfitLoss	259000000	USD
	us-gaap	Profit Loss ProfitLoss	929000000	USD
CY2020Q3	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	0	USD
CY2019Q3	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	2000000	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	1000000	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	5000000	USD
CY2020Q3	us-gaap	Dividends Preferred Stock Stock DividendsPreferredStockStock	8000000	USD
CY2019Q3	us-gaap	Dividends Preferred Stock Stock DividendsPreferredStockStock	0	USD
	us-gaap	Dividends Preferred Stock Stock DividendsPreferredStockStock	8000000	USD
	us-gaap	Dividends Preferred Stock Stock DividendsPreferredStockStock	0	USD
CY2020Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	203000000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	290000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	250000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	924000000	USD
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.45
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.98
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.79
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.08
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.44
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.96
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.78
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.02
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	169000000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	338000000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	610000000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1202000000	USD
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	94000000	USD
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	97000000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	284000000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	302000000	USD
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.68
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.67
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.04
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.01
CY2019Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7323000000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	292000000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	46000000	USD
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.67
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	97000000	USD
CY2019Q3	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	370000000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1000000	USD
CY2019Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	5000000	USD
CY2019Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7200000000	USD
CY2020Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7802000000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	211000000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-42000000	USD
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.68
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	94000000	USD
CY2020Q3	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	8000000	USD
CY2020Q3	us-gaap	Stock And Warrants Issued During Period Value Preferred Stock And Warrants StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants	-1000000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	0	USD
CY2020Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	6000000	USD
CY2020Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7874000000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7507000000	USD
CY2019Q1	cma	Cumulative Effect Of Change In Accounting Principle CumulativeEffectOfChangeInAccountingPrinciple	-14000000	USD
	us-gaap	Profit Loss ProfitLoss	929000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	273000000	USD
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.01
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	302000000	USD
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	1229000000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1000000	USD
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	37000000	USD
CY2019Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7200000000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7327000000	USD
CY2020Q1	cma	Cumulative Effect Of Change In Accounting Principle CumulativeEffectOfChangeInAccountingPrinciple	13000000	USD
	us-gaap	Profit Loss ProfitLoss	259000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	351000000	USD
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.04
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	284000000	USD
	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	8000000	USD
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	194000000	USD
	us-gaap	Stock And Warrants Issued During Period Value Preferred Stock And Warrants StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants	394000000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	2000000	USD
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	18000000	USD
CY2020Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	7874000000	USD
	us-gaap	Profit Loss ProfitLoss	259000000	USD
	us-gaap	Profit Loss ProfitLoss	929000000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	554000000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	66000000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-104000000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	4000000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	82000000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	84000000	USD
	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	-19000000	USD
	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	-23000000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	18000000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	37000000	USD
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-7000000	USD
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-2000000	USD
	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	0	USD
	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	-8000000	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	1000000	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	0	USD
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	-32000000	USD
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	-1000000	USD
	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	-50000000	USD
	us-gaap	Increase Decrease In Accrued Liabilities IncreaseDecreaseInAccruedLiabilities	-39000000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	58000000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	200000000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	720000000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	869000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2344000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1615000000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	0	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	987000000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	4796000000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	2721000000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	2185000000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	1419000000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	3000000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	1000000	USD
	cma	Net Increase In Fixed Assets NetIncreaseInFixedAssets	51000000	USD
	cma	Net Increase In Fixed Assets NetIncreaseInFixedAssets	62000000	USD
	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	51000000	USD
	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	201000000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	92000000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	201000000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	14000000	USD
	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	7000000	USD
	cma	Increase Decrease In Other Investing Assets And Liabilities Net IncreaseDecreaseInOtherInvestingAssetsAndLiabilitiesNet	0	USD
	cma	Increase Decrease In Other Investing Assets And Liabilities Net IncreaseDecreaseInOtherInvestingAssetsAndLiabilitiesNet	2000000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-4630000000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1590000000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	11054000000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1105000000	USD
	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-61000000	USD
	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	7000000	USD
	us-gaap	Repayments Of Debt RepaymentsOfDebt	1675000000	USD
	us-gaap	Repayments Of Debt RepaymentsOfDebt	350000000	USD
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1050000000	USD
	us-gaap	Stock And Warrants Issued During Period Value Preferred Stock And Warrants StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants	394000000	USD
	us-gaap	Stock And Warrants Issued During Period Value Preferred Stock And Warrants StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants	0	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	199000000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1242000000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	282000000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	303000000	USD
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	2000000	USD
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	12000000	USD
	cma	Increase Decrease In Other Financing Assets And Liabilities Net IncreaseDecreaseInOtherFinancingAssetsAndLiabilitiesNet	0	USD
	cma	Increase Decrease In Other Financing Assets And Liabilities Net IncreaseDecreaseInOtherFinancingAssetsAndLiabilitiesNet	-2000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	9233000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	277000000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	5323000000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-444000000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	5818000000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	4561000000	USD
CY2020Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	11141000000	USD
CY2019Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	4117000000	USD
	us-gaap	Interest Paid InterestPaid	186000000	USD
	us-gaap	Interest Paid InterestPaid	347000000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	133000000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	221000000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	1000000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	3000000	USD
CY2019Q4	cma	Overallallowanceforcreditlosses Overallallowanceforcreditlosses	668000000	USD
CY2019Q4	cma	Businessloanspercentofportfolio Businessloanspercentofportfolio	0.91
CY2020Q1	cma	Increaseinretailloansallowanceforcreditlosses Increaseinretailloansallowanceforcreditlosses	25000000	USD
CY2020Q3	cma	Libo Rloanspercentofportfolio LIBORloanspercentofportfolio	0.72
CY2020Q3	cma	Percentofloanportfoliowithinterestrateswapstoconvertvariable Lbio Rtofixedrates PercentofloanportfoliowithinterestrateswapstoconvertvariableLBIORtofixedrates	0.10
CY2020Q3	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	14758000000	USD
CY2020Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	334000000	USD
CY2020Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	2000000	USD
CY2020Q3	us-gaap	Available For Sale Securities AvailableForSaleSecurities	15090000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	12313000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	113000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	28000000	USD
CY2019Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	12398000000	USD
CY2020Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	980000000	USD
CY2020Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	2000000	USD
CY2020Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	0	USD
CY2020Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2020Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	980000000	USD
CY2020Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	2000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	1494000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	7000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	1906000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	21000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	3400000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	28000000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	5300000000	USD
CY2020Q3	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	4800000000	USD
CY2020Q3	us-gaap	Debt Instrument Unused Borrowing Capacity Amount DebtInstrumentUnusedBorrowingCapacityAmount	4600000000	USD
CY2020Q3	us-gaap	Securities Borrowed Liability SecuritiesBorrowedLiability	522000000	USD
CY2020Q3	cma	Liabilities Secured By Pledged Securities LiabilitiesSecuredByPledgedSecurities	439000000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	411000000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest	322000000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	51636000000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	52369000000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	153000000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	153000000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest	199000000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest	199000000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	50017000000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	50369000000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	50369000000	USD
CY2020Q3	us-gaap	Financing Receivable Originated In Current Fiscal Year FinancingReceivableOriginatedInCurrentFiscalYear	8171000000	USD
CY2020Q3	us-gaap	Financing Receivable Originated In Fiscal Year Before Latest Fiscal Year FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear	6236000000	USD
CY2020Q3	us-gaap	Financing Receivable Originated Two Years Before Latest Fiscal Year FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear	4869000000	USD
CY2020Q3	us-gaap	Financing Receivable Originated Three Years Before Latest Fiscal Year FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear	3629000000	USD
CY2020Q3	us-gaap	Financing Receivable Originated Four Years Before Latest Fiscal Year FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear	2216000000	USD
CY2020Q3	us-gaap	Financing Receivable Originated Five Or More Years Before Latest Fiscal Year FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear	4817000000	USD
CY2020Q3	us-gaap	Financing Receivable Revolving FinancingReceivableRevolving	22336000000	USD
CY2020Q3	us-gaap	Financing Receivable Revolving Converted To Term Loan FinancingReceivableRevolvingConvertedToTermLoan	95000000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	52369000000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	50369000000	USD
CY2020Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	1066000000	USD
CY2019Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	688000000	USD
CY2020Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	5000000	USD
CY2019Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	35000000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	1038000000	USD
CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	681000000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	668000000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	701000000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	554000000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	66000000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	1038000000	USD
CY2019Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	681000000	USD
CY2020Q3	cma	Financing Receivable Ratio Of Allowance For Credit Losses To All Loans FinancingReceivableRatioOfAllowanceForCreditLossesToAllLoans	0.0198
CY2019Q3	cma	Financing Receivable Ratio Of Allowance For Credit Losses To All Loans FinancingReceivableRatioOfAllowanceForCreditLossesToAllLoans	0.0132
CY2020Q3	cma	Financing Receivable Ratio Of Allowance For Loan Losses To All Loans Excluding Ppp Loans FinancingReceivableRatioOfAllowanceForLoanLossesToAllLoansExcludingPPPLoans	0.0214
CY2019Q3	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
CY2020Q3	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
CY2020Q3	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	107000000	USD
CY2020Q3	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	215000000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest	322000000	USD
CY2019Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	69000000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	130000000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Impaired Nonperforming Nonaccrual Of Interest LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest	199000000	USD
CY2020Q3	us-gaap	Foreclosed Assets ForeclosedAssets	10000000	USD
CY2019Q4	us-gaap	Foreclosed Assets ForeclosedAssets	11000000	USD
CY2019Q4	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	0	USD
CY2020Q3	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	0	USD
CY2020Q3	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	13000000	USD
CY2019Q3	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	11000000	USD
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	29000000	USD
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	20000000	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	1000000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	3000000	USD
CY2020Q3	cma	Derivative Assets Cash Collateral DerivativeAssetsCashCollateral	133000000	USD
CY2020Q3	us-gaap	Derivative Asset Fair Value Of Collateral DerivativeAssetFairValueOfCollateral	51000000	USD
CY2020Q3	cma	Cash Collateral Posted For Derivatives In Liability Position CashCollateralPostedForDerivativesInLiabilityPosition	37000000	USD
CY2020Q3	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	0	USD
CY2020Q3	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	34474000000	USD
CY2020Q3	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	825000000	USD
CY2020Q3	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	287000000	USD
CY2019Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	30134000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	317000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	141000000	USD
CY2020Q3	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	72000000	USD
CY2020Q3	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	72000000	USD
CY2019Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	63000000	USD
CY2019Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	63000000	USD
CY2020Q3	us-gaap	Derivative Asset Collateral Obligation To Return Cash Offset DerivativeAssetCollateralObligationToReturnCashOffset	118000000	USD
CY2020Q3	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	36000000	USD
CY2019Q4	us-gaap	Derivative Asset Collateral Obligation To Return Cash Offset DerivativeAssetCollateralObligationToReturnCashOffset	11000000	USD
CY2019Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	12000000	USD
CY2020Q3	us-gaap	Derivative Assets DerivativeAssets	635000000	USD
CY2020Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	179000000	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	243000000	USD
CY2019Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	66000000	USD
CY2020Q3	us-gaap	Derivative Collateral Obligation To Return Securities DerivativeCollateralObligationToReturnSecurities	0	USD
CY2020Q3	us-gaap	Derivative Collateral Right To Reclaim Securities DerivativeCollateralRightToReclaimSecurities	48000000	USD
CY2019Q4	us-gaap	Derivative Collateral Obligation To Return Securities DerivativeCollateralObligationToReturnSecurities	0	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Securities DerivativeCollateralRightToReclaimSecurities	21000000	USD
CY2020Q3	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	635000000	USD
CY2020Q3	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	131000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	243000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral	45000000	USD
CY2020Q3	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Assets DerivativeCreditRiskValuationAdjustmentDerivativeAssets	31000000	USD
CY2019Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Assets DerivativeCreditRiskValuationAdjustmentDerivativeAssets	9000000	USD
CY2020Q3	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	11000000	USD
CY2019Q3	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	50000000	USD
	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	70000000	USD
	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	152000000	USD
CY2019Q4	cma	Carrying Value Of Unused Commitments To Extend Credit CarryingValueOfUnusedCommitmentsToExtendCredit	25000000	USD
	cma	Longest Expiration Year Letters Of Credit LongestExpirationYearLettersOfCredit	2028
CY2020Q3	cma	Risk Participations Covering Standby And Commercial Letters Of Credit RiskParticipationsCoveringStandbyAndCommercialLettersOfCredit	169000000	USD
	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	0	USD
CY2020Q3	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	0	USD
	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	0	USD
CY2019Q3	us-gaap	Gain Loss On Foreign Currency Derivative Instruments Not Designated As Hedging Instruments GainLossOnForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstruments	0	USD
CY2020Q3	cma	Allowance For Off Balance Sheet Credit Losses AllowanceForOffBalanceSheetCreditLosses	60000000	USD
CY2019Q4	cma	Allowance For Off Balance Sheet Credit Losses AllowanceForOffBalanceSheetCreditLosses	31000000	USD
CY2020Q3	cma	Carrying Value Of Unused Commitments To Extend Credit CarryingValueOfUnusedCommitmentsToExtendCredit	50000000	USD
CY2019Q4	cma	Risk Participations Covering Standby And Commercial Letters Of Credit RiskParticipationsCoveringStandbyAndCommercialLettersOfCredit	161000000	USD
CY2020Q3	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	3200000000	USD
CY2019Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	3300000000	USD
CY2020Q3	cma	Carrying Value Of Standby And Commercial Letters Of Credit CarryingValueOfStandbyAndCommercialLettersOfCredit	35000000	USD
CY2020Q3	cma	Carrying Value Of Standby And Commercial Letters Of Credit Included In Deferred Fees CarryingValueOfStandbyAndCommercialLettersOfCreditIncludedInDeferredFees	25000000	USD
CY2020Q3	cma	Carrying Value Of Standby And Commercial Letters Of Credit Included In Allowance For Credit Losses On Lending Related Commitments CarryingValueOfStandbyAndCommercialLettersOfCreditIncludedInAllowanceForCreditLossesOnLendingRelatedCommitments	10000000	USD
CY2019Q4	cma	Carrying Value Of Standby And Commercial Letters Of Credit CarryingValueOfStandbyAndCommercialLettersOfCredit	32000000	USD
CY2019Q4	cma	Carrying Value Of Standby And Commercial Letters Of Credit Included In Deferred Fees CarryingValueOfStandbyAndCommercialLettersOfCreditIncludedInDeferredFees	26000000	USD
CY2019Q4	cma	Carrying Value Of Standby And Commercial Letters Of Credit Included In Allowance For Credit Losses On Lending Related Commitments CarryingValueOfStandbyAndCommercialLettersOfCreditIncludedInAllowanceForCreditLossesOnLendingRelatedCommitments	6000000	USD
CY2020Q3	cma	Total Internally Classified Watch List Letters Of Credit TotalInternallyClassifiedWatchListLettersOfCredit	91000000	USD
CY2019Q4	cma	Total Internally Classified Watch List Letters Of Credit TotalInternallyClassifiedWatchListLettersOfCredit	44000000	USD
CY2020Q3	cma	Watch List Letters Of Credit As Percentage Of Total Letters Of Credit WatchListLettersOfCreditAsPercentageOfTotalLettersOfCredit	0.028
CY2019Q4	cma	Watch List Letters Of Credit As Percentage Of Total Letters Of Credit WatchListLettersOfCreditAsPercentageOfTotalLettersOfCredit	0.013
CY2020Q3	cma	Notional Amount Of Derivative Credit Risk Participation Agreements NotionalAmountOfDerivativeCreditRiskParticipationAgreements	1100000000	USD
CY2019Q4	cma	Notional Amount Of Derivative Credit Risk Participation Agreements NotionalAmountOfDerivativeCreditRiskParticipationAgreements	786000000	USD
CY2020Q3	cma	Fair Value Amount Of Derivative Credit Risk Participation Agreements FairValueAmountOfDerivativeCreditRiskParticipationAgreements	3000000	USD
CY2020Q3	us-gaap	Credit Derivative Maximum Exposure Undiscounted CreditDerivativeMaximumExposureUndiscounted	71000000	USD
CY2019Q4	us-gaap	Credit Derivative Maximum Exposure Undiscounted CreditDerivativeMaximumExposureUndiscounted	20000000	USD
CY2020Q3	us-gaap	Variable Interest Entity Activity Between Vie And Entity Expense VariableInterestEntityActivityBetweenVIEAndEntityExpense	171000000	USD
	us-gaap	Variable Interest Entity Financial Or Other Support Amount VariableInterestEntityFinancialOrOtherSupportAmount	0	USD
	us-gaap	Variable Interest Entity Financial Or Other Support Amount VariableInterestEntityFinancialOrOtherSupportAmount	0	USD
CY2020Q3	us-gaap	Long Term Debt LongTermDebt	5754000000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	7269000000	USD
CY2020Q3	us-gaap	Federal Home Loan Bank Advances Weighted Average Interest Rate FederalHomeLoanBankAdvancesWeightedAverageInterestRate	0.0022
CY2020Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged For Federal Home Loan Bank Debt PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedForFederalHomeLoanBankDebt	19000000000.0	USD
CY2020Q3	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	4800000000	USD
CY2020Q3	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	2800000000	USD
CY2020Q3	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	11700000000	USD
CY2020Q3	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	10000000	USD
CY2019Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	12000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	65000000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-138000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	247000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	267000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	58000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	62000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	189000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	205000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-8000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-2000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-6000000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	189000000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	211000000	USD
CY2020Q3	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	254000000	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	73000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax	34000000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax	0	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	232000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	69000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	56000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	16000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	176000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	53000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	46000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax	-1000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	12000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	0	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	34000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-1000000	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	142000000	USD
	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	54000000	USD
CY2020Q3	us-gaap	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax	176000000	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax	54000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	-334000000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	-471000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-47000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax	-30000000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	-21000000	USD
	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	-20000000	USD
	cma	Other Comprehensive Income Loss Reclassification Adjustment Pension And Other Postretirement Benefit Plans Recognized In Net Periodic Defined Benefit Cost Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentPensionAndOtherPostretirementBenefitPlansRecognizedInNetPeriodicDefinedBenefitCostBeforeTax	26000000	USD
	cma	Other Comprehensive Income Loss Reclassification Adjustment Pension And Other Postretirement Benefit Plans Recognized In Net Periodic Defined Benefit Cost Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentPensionAndOtherPostretirementBenefitPlansRecognizedInNetPeriodicDefinedBenefitCostBeforeTax	10000000	USD
	cma	Other Comprehensive Income Loss Reclassification Adjustment Pension And Other Postretirement Benefit Plans Recognized In Net Periodic Defined Benefit Cost Tax OtherComprehensiveIncomeLossReclassificationAdjustmentPensionAndOtherPostretirementBenefitPlansRecognizedInNetPeriodicDefinedBenefitCostTax	6000000	USD
	cma	Other Comprehensive Income Loss Reclassification Adjustment Pension And Other Postretirement Benefit Plans Recognized In Net Periodic Defined Benefit Cost Tax OtherComprehensiveIncomeLossReclassificationAdjustmentPensionAndOtherPostretirementBenefitPlansRecognizedInNetPeriodicDefinedBenefitCostTax	2000000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-20000000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-8000000	USD
CY2020Q3	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	-314000000	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	-463000000	USD
CY2020Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	116000000	USD
CY2019Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-336000000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	211000000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	292000000	USD
	us-gaap	Profit Loss ProfitLoss	259000000	USD
	us-gaap	Profit Loss ProfitLoss	929000000	USD
CY2020Q3	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	0	USD
CY2019Q3	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	2000000	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	1000000	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	5000000	USD
CY2020Q3	us-gaap	Dividends Preferred Stock DividendsPreferredStock	8000000	USD
CY2019Q3	us-gaap	Dividends Preferred Stock DividendsPreferredStock	0	USD
	us-gaap	Dividends Preferred Stock DividendsPreferredStock	8000000	USD
	us-gaap	Dividends Preferred Stock DividendsPreferredStock	0	USD
CY2020Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	203000000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	290000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	250000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	924000000	USD
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	139000000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	147000000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	139000000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	152000000	shares
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.45
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.98
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.79
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.08
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	139000000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	147000000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	139000000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	152000000	shares
CY2020Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1000000	shares
CY2019Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1000000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1000000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2000000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	140000000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	148000000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	140000000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	154000000	shares
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.44
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.96
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.78
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.02
CY2020Q3	cma	Stockoptionsexcludedbecauseexercisepricesweregreaterthanaveragemarketpriceofshares Stockoptionsexcludedbecauseexercisepricesweregreaterthanaveragemarketpriceofshares	2029000	shares
CY2019Q3	cma	Stockoptionsexcludedbecauseexercisepricesweregreaterthanaveragemarketpriceofshares Stockoptionsexcludedbecauseexercisepricesweregreaterthanaveragemarketpriceofshares	814000	shares
	cma	Stockoptionsexcludedbecauseexercisepricesweregreaterthanaveragemarketpriceofshares Stockoptionsexcludedbecauseexercisepricesweregreaterthanaveragemarketpriceofshares	1497000	shares
	cma	Stockoptionsexcludedbecauseexercisepricesweregreaterthanaveragemarketpriceofshares Stockoptionsexcludedbecauseexercisepricesweregreaterthanaveragemarketpriceofshares	570000	shares
CY2020Q3	cma	Depositary Shares Issued DepositarySharesIssued	400000	shares
	us-gaap	Preferred Stock Dividend Rate Percentage PreferredStockDividendRatePercentage	0.05625
CY2020Q3	us-gaap	Preferred Stock Liquidation Preference Value PreferredStockLiquidationPreferenceValue	100000	USD
CY2020Q3	us-gaap	Preferred Stock Liquidation Preference PreferredStockLiquidationPreference	1000
	us-gaap	Proceeds From Issuance Of Preferred Stock Preference Stock And Warrants ProceedsFromIssuanceOfPreferredStockPreferenceStockAndWarrants	400000000	USD
CY2020Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	18000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	17000000	USD
	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	1000000	USD
CY2020Q3	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	6000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	8000000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	34000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	42000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	3000000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	3000000	USD
CY2020Q3	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	3000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	3000000	USD
CY2020Q3	us-gaap	Legal Fees LegalFees	5000000	USD
CY2019Q3	us-gaap	Legal Fees LegalFees	5000000	USD
	us-gaap	Legal Fees LegalFees	12000000	USD
	us-gaap	Legal Fees LegalFees	10000000	USD
	cma	Number Of Major Business Segments NumberOfMajorBusinessSegments	3	segments
	cma	Number Of Major Business Segments NumberOfMajorBusinessSegments	3	segments
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	458000000	USD
CY2020Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	5000000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	252000000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	446000000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	48000000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	211000000	USD
CY2020Q3	cma	Net Credit Related Charge Offs NetCreditRelatedChargeOffs	33000000	USD
CY2020Q3	cma	Segment Reporting Average Assets SegmentReportingAverageAssets	84268000000	USD
CY2020Q3	cma	Average Balance During Period Loans And Leases Receivable Net Of Deferred Income AverageBalanceDuringPeriodLoansAndLeasesReceivableNetOfDeferredIncome	52013000000	USD
CY2020Q3	cma	Average Balance During Period Deposits AverageBalanceDuringPeriodDeposits	68763000000	USD
CY2020Q3	cma	Return On Average Assets ReturnOnAverageAssets	0.0099
CY2020Q3	cma	Efficiency Ratio EfficiencyRatio	0.6279
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	586000000	USD
CY2019Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	35000000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	256000000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	435000000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	80000000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	292000000	USD
CY2019Q3	cma	Net Credit Related Charge Offs NetCreditRelatedChargeOffs	42000000	USD
CY2019Q3	cma	Segment Reporting Average Assets SegmentReportingAverageAssets	71736000000	USD
CY2019Q3	cma	Average Balance During Period Loans And Leases Receivable Net Of Deferred Income AverageBalanceDuringPeriodLoansAndLeasesReceivableNetOfDeferredIncome	50887000000	USD
CY2019Q3	cma	Average Balance During Period Deposits AverageBalanceDuringPeriodDeposits	55716000000	USD
CY2019Q3	cma	Return On Average Assets ReturnOnAverageAssets	0.0161
CY2019Q3	cma	Efficiency Ratio EfficiencyRatio	0.5154
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	1442000000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	554000000	USD
	us-gaap	Noninterest Income NoninterestIncome	736000000	USD
	us-gaap	Noninterest Expense NoninterestExpense	1311000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	54000000	USD
	us-gaap	Profit Loss ProfitLoss	259000000	USD
	cma	Net Credit Related Charge Offs NetCreditRelatedChargeOffs	167000000	USD
	cma	Segment Reporting Average Assets SegmentReportingAverageAssets	79742000000	USD
	cma	Average Balance During Period Loans And Leases Receivable Net Of Deferred Income AverageBalanceDuringPeriodLoansAndLeasesReceivableNetOfDeferredIncome	51706000000	USD
	cma	Average Balance During Period Deposits AverageBalanceDuringPeriodDeposits	63291000000	USD
	cma	Return On Average Assets ReturnOnAverageAssets	0.0043
	cma	Efficiency Ratio EfficiencyRatio	0.6010
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	1795000000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	66000000	USD
	us-gaap	Noninterest Income NoninterestIncome	744000000	USD
	us-gaap	Noninterest Expense NoninterestExpense	1292000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	252000000	USD
	us-gaap	Profit Loss ProfitLoss	929000000	USD
	cma	Net Credit Related Charge Offs NetCreditRelatedChargeOffs	86000000	USD
	cma	Segment Reporting Average Assets SegmentReportingAverageAssets	70927000000	USD
	cma	Average Balance During Period Loans And Leases Receivable Net Of Deferred Income AverageBalanceDuringPeriodLoansAndLeasesReceivableNetOfDeferredIncome	50514000000	USD
	cma	Average Balance During Period Deposits AverageBalanceDuringPeriodDeposits	54909000000	USD
	cma	Return On Average Assets ReturnOnAverageAssets	0.0175
	cma	Efficiency Ratio EfficiencyRatio	0.5066
	cma	Number Of Geographic Markets NumberOfGeographicMarkets	3	markets
	cma	Number Of Geographic Markets NumberOfGeographicMarkets	3	markets
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	458000000	USD
CY2020Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	5000000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	252000000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	446000000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	48000000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	211000000	USD
CY2020Q3	cma	Net Credit Related Charge Offs NetCreditRelatedChargeOffs	33000000	USD
CY2020Q3	cma	Segment Reporting Average Assets SegmentReportingAverageAssets	84268000000	USD
CY2020Q3	cma	Average Balance During Period Loans And Leases Receivable Net Of Deferred Income AverageBalanceDuringPeriodLoansAndLeasesReceivableNetOfDeferredIncome	52013000000	USD
CY2020Q3	cma	Average Balance During Period Deposits AverageBalanceDuringPeriodDeposits	68763000000	USD
CY2020Q3	cma	Return On Average Assets ReturnOnAverageAssets	0.0099
CY2020Q3	cma	Efficiency Ratio EfficiencyRatio	0.6279
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	586000000	USD
CY2019Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	35000000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	256000000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	435000000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	80000000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	292000000	USD
CY2019Q3	cma	Net Credit Related Charge Offs NetCreditRelatedChargeOffs	42000000	USD
CY2019Q3	cma	Segment Reporting Average Assets SegmentReportingAverageAssets	71736000000	USD
CY2019Q3	cma	Average Balance During Period Loans And Leases Receivable Net Of Deferred Income AverageBalanceDuringPeriodLoansAndLeasesReceivableNetOfDeferredIncome	50887000000	USD
CY2019Q3	cma	Average Balance During Period Deposits AverageBalanceDuringPeriodDeposits	55716000000	USD
CY2019Q3	cma	Return On Average Assets ReturnOnAverageAssets	0.0161
CY2019Q3	cma	Efficiency Ratio EfficiencyRatio	0.5154
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	1442000000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	554000000	USD
	us-gaap	Noninterest Income NoninterestIncome	736000000	USD
	us-gaap	Noninterest Expense NoninterestExpense	1311000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	54000000	USD
	us-gaap	Profit Loss ProfitLoss	259000000	USD
	cma	Net Credit Related Charge Offs NetCreditRelatedChargeOffs	167000000	USD
	cma	Segment Reporting Average Assets SegmentReportingAverageAssets	79742000000	USD
	cma	Average Balance During Period Loans And Leases Receivable Net Of Deferred Income AverageBalanceDuringPeriodLoansAndLeasesReceivableNetOfDeferredIncome	51706000000	USD
	cma	Average Balance During Period Deposits AverageBalanceDuringPeriodDeposits	63291000000	USD
	cma	Return On Average Assets ReturnOnAverageAssets	0.0043
	cma	Efficiency Ratio EfficiencyRatio	0.6010
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	1795000000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	66000000	USD
	us-gaap	Noninterest Income NoninterestIncome	744000000	USD
	us-gaap	Noninterest Expense NoninterestExpense	1292000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	252000000	USD
	us-gaap	Profit Loss ProfitLoss	929000000	USD
	cma	Net Credit Related Charge Offs NetCreditRelatedChargeOffs	86000000	USD
	cma	Segment Reporting Average Assets SegmentReportingAverageAssets	70927000000	USD
	cma	Average Balance During Period Loans And Leases Receivable Net Of Deferred Income AverageBalanceDuringPeriodLoansAndLeasesReceivableNetOfDeferredIncome	50514000000	USD
	cma	Average Balance During Period Deposits AverageBalanceDuringPeriodDeposits	54909000000	USD
	cma	Return On Average Assets ReturnOnAverageAssets	0.0175
	cma	Efficiency Ratio EfficiencyRatio	0.5066
CY2020Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	193000000	USD
CY2020Q3	cma	Othersourcesofnoninterestincome Othersourcesofnoninterestincome	59000000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	252000000	USD
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	190000000	USD
CY2019Q3	cma	Othersourcesofnoninterestincome Othersourcesofnoninterestincome	66000000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	256000000	USD
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	566000000	USD
	cma	Othersourcesofnoninterestincome Othersourcesofnoninterestincome	170000000	USD
	us-gaap	Noninterest Income NoninterestIncome	736000000	USD
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	563000000	USD
	cma	Othersourcesofnoninterestincome Othersourcesofnoninterestincome	181000000	USD
	us-gaap	Noninterest Income NoninterestIncome	744000000	USD
CY2020Q3	us-gaap	Preferred Stock Value PreferredStockValue	394000000	USD

Files In Submission

Name	View Source	Status
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0000028412-20-000105-index.html	Edgar Link	pending
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cma-20200930.htm	Edgar Link	pending
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$CMA
COMERICA INC /NEW/ Stock $cma

2020 Q4 Form 10-Q Financial Statement

#000002841220000105 Filed on October 30, 2020

Income Statement

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Facts In Submission

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$CMA COMERICA INC /NEW/ Stock $cma

2020 Q4 Form 10-Q Financial Statement

#000002841220000105 Filed on October 30, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CMA
COMERICA INC /NEW/ Stock $cma