XML 91 R73.htm IDEA: XBRL DOCUMENT v3.22.0.1

Credit Quality And Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Loan interest receivable	$ 120	$ 141
Financing Receivable, Nonaccrual, Interest Income	0	0
Foreclosed property	1	8
Retail loans secured by residential real estate in process of foreclosure	0	0
Commitments to lend additional funds to TDR borrowers	0	0
Loans with terms extended in accordance with CARES Act	$ 22	$ 72
Principal deferrals
Minimum period loan terms were extended	90 days	90 days
Subsequent default during period	$ 0	$ 10
Interest Rate Reductions
Minimum period loan terms were extended	90 days	90 days
Subsequent default during period	$ 0	$ 0

X

- Definition

Days that a principal or interest payment is past due to be defined as a subsequent default

+ References

No definition available.

+ Details

Name:	cma_Dayspastduedefinedassubsequentdefault
Namespace Prefix:	cma_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Loan interest receivable

+ References

No definition available.

+ Details

Name:	cma_LoanInterestReceivable
Namespace Prefix:	cma_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Loans with terms extended in accordance with CARES Act

+ References

No definition available.

+ Details

Name:	cma_LoansWithTermsExtendedInAccordanceWithCARESAct
Namespace Prefix:	cma_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

+ Details

Name:	us-gaap_FinancingReceivableNonaccrualInterestIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5162-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4437-111522

+ Details

Name:	us-gaap_ForeclosedAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

+ Details

Name:	us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL49126937-111524

+ Details

Name:	us-gaap_MortgageLoansInProcessOfForeclosureAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=us-gaap_PaymentDeferralMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=us-gaap_ContractualInterestRateReductionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: