Financing receivable, allowance for credit loss, excluding accrued interest, beginning of period

No definition available.

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Namespace Prefix:	cma_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Financing receivable, allowance for credit loss, excluding accrued interest, end of period

+ References

No definition available.

+ Details

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Namespace Prefix:	cma_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The ratio of Allowance for Credit Losses to All Loans.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

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-Name Accounting Standards Codification
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Period Type:	instant

- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

+ References

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Period Type:	duration

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

+ References

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Balance Type:	debit
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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

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Credit Quality And Allowance For Credit Losses (Changes In The Allowance For Loan Losses And Related Loan Amounts) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 698		$ 698			$ 690
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest, Current					$ 719	725	$ 728	$ 728
Provision for credit losses	44	$ 0	64	$ 14
Financing receivable, allowance for credit loss, excluding accrued interest, end of period	$ 735	$ 717	$ 735	$ 717
As a percentage of total loans	1.44%	1.38%	1.44%	1.38%
Financing Receivable
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Loan charge-offs	$ (31)	$ (28)	$ (63)	$ (49)
Recoveries on loans previously charged-off	3	17	9	24
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery)	28	11	54	25
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	698	686	698	686	683	690	691	688
Provision for credit losses	$ 43	$ 6	$ 62	$ 23
As a percentage of total loans	1.36%	1.32%	1.36%	1.32%
Unused Commitments to Extend Credit
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 37	$ 31	$ 37	$ 31	36	35	37	40
Provision for credit losses	1	(6)	2	(9)
Business loans:
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	680	643	680	643	659	653	654	651
Provision for credit losses	$ 50	$ 1	$ 81	$ 18
As a percentage of total loans	1.45%	1.35%	1.45%	1.35%
Business loans: \| Financing Receivable
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Loan charge-offs	$ (30)	$ (28)	$ (61)	$ (48)
Recoveries on loans previously charged-off	1	16	7	22
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery)	29	12	54	26
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	654	620	654	620	634	625	626	620
Provision for credit losses	$ 49	$ 6	$ 83	$ 26
As a percentage of total loans	1.39%	1.30%	1.39%	1.30%
Business loans: \| Unused Commitments to Extend Credit
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 26	$ 23	$ 26	$ 23	25	28	28	31
Provision for credit losses	1	(5)	(2)	(8)
Retail loans:
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	55	74	55	74	60	72	74	77
Provision for credit losses	$ (6)	$ (1)	$ (17)	$ (4)
As a percentage of total loans	1.31%	1.79%	1.31%	1.79%
Retail loans: \| Financing Receivable
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Loan charge-offs	$ (1)	$ 0	$ (2)	$ (1)
Recoveries on loans previously charged-off	2	1	2	2
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery)	(1)	(1)	0	(1)
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	44	66	44	66	49	65	65	68
Provision for credit losses	$ (6)	$ 0	$ (21)	$ (3)
As a percentage of total loans	1.06%	1.59%	1.06%	1.59%
Retail loans: \| Unused Commitments to Extend Credit
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 11	$ 8	$ 11	$ 8	$ 11	$ 7	$ 9	$ 9
Provision for credit losses	$ 0	$ (1)	$ 4	$ (1)