XML 62 R52.htm IDEA: XBRL DOCUMENT
v3.25.2

Credit Quality And Allowance For Credit Losses (Financial Effect of Loan Modifications) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 23 months | 12 months | 21 months |  | 13 months
Weighted-Average Interest Rate Reduction |  | (2.05%) | 1.31% | (2.11%) |  | (1.34%)
Financing receivable, modified, past due |  | $ 5 |  | $ 22 |  |
Payment Delay |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Minimum period loan terms were extended |  | 90 days | 90 days | 90 days |  | 90 days
Interest Rate Reduction |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Minimum period loan terms were extended |  | 90 days | 90 days | 90 days |  | 90 days
Business loans: |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 16 months | 12 months | 17 months |  | 12 months
Weighted-Average Interest Rate Reduction |  | (2.97%) | 1.03% | (2.97%) |  | (1.06%)
Business loans: | Commercial |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 16 months | 13 months | 16 months |  | 12 months
Weighted-Average Interest Rate Reduction |  | 0.00% | 1.03% | 0.00% |  | (1.06%)
Business loans: | Commercial | International |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  |  | 8 months |  |  | 9 months
Weighted-Average Interest Rate Reduction |  |  |  |  |  | 0.00%
Retail loans: | Consumer |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 120 months |  | 120 months |  | 118 months
Weighted-Average Interest Rate Reduction |  | 0.83% | 4.17% | 1.11% |  | 3.54%
Commercial mortgage: | Business loans: | Commercial |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 14 months | 7 months | 20 months |  | 9 months
Weighted-Average Interest Rate Reduction |  | 0.00% | 0.00% | 0.00% |  | 0.00%
Commercial mortgage: | Business loans: | Commercial | Commercial |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 12 months |  | 20 months |  |
Weighted-Average Interest Rate Reduction |  | 0.00% |  | 0.00% |  |
Commercial mortgage: | Business loans: | Commercial | Other business lines |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  | 18 months | 7 months | 20 months | [1] | 9 months
Weighted-Average Interest Rate Reduction | [1] | 0.00% | 0.00% | 0.00% |  | 0.00%
Home equity | Retail loans: | Consumer |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  |  |  |  |  | 118 months
Weighted-Average Interest Rate Reduction |  | (4.26%) | (4.17%) | (3.73%) |  | (3.54%)
Consumer Loan | Retail loans: | Consumer |  |  |  |  |  |
Financing Receivable, Troubled Debt Restructuring [Line Items] |  |  |  |  |  |
Weighted-Average Term Extension (in months) |  |  |  |  |  | 118 months
Weighted-Average Interest Rate Reduction |  | 4.26% | 4.17% | 3.73% |  | 3.54%
[1] | Primarily loans secured by owner-occupied real estate.

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 Financing receivable, modified, past due + References No definition available. + Details
Name: | cma_FinancingReceivableModifiedPastDue
Namespace Prefix: | cma_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 34 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-34 Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 33 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-33 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
Name: | us-gaap_FinancingReceivableModificationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A + Details
Name: | us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A + Details
Name: | us-gaap_FinancingReceivableModifiedWeightedAverageTermIncreaseFromModification
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfFinancingReceivableTypeOfBorrowerAxis=us-gaap_CommercialBorrowerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GeographicDistributionAxis=us-gaap_NonUsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfFinancingReceivableTypeOfBorrowerAxis=us-gaap_ConsumerBorrowerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_RealEstateLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=us-gaap_RealEstateSectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=us-gaap_CommercialAndIndustrialSectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HomeEquityLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConsumerLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |