XML 72 R61.htm IDEA: XBRL DOCUMENT
v3.25.3

Allowance for Credit Losses and Reserve for Unfunded Lending Commitments - Summary of Loss Sharing Arrangements (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Change in estimated partner reimbursements that (increased) decreased provision for credit losses | $ 2,714 | $ 2,482 | $ 16,513 | $ 9,074
Loss sharing agreements |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Estimated reimbursements from partners, beginning of period | 1,191 | 1,210 | 1,010 | 2,014
Amounts due from partners for charged off loans | (154) | (157) | (491) | (734)
Change in estimated partner reimbursements that (increased) decreased provision for credit losses | 95 | 102 | 613 | (125)
Estimated reimbursements from partners, end of period | $ 1,132 | $ 1,155 | $ 1,132 | $ 1,155

X
- Definition Loss Sharing Agreements, Financing Receivable, Allowance, Covered, Expected Reimbursement + References No definition available. + Details
Name: | cof_LossSharingAgreementsFinancingReceivableAllowanceCoveredExpectedReimbursement
Namespace Prefix: | cof_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of writeoff of financing receivable, charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11B -Subparagraph (c)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-6 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of credit loss expense (reversal of expense) for financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-22 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(11)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1 + Details
Name: | us-gaap_ProvisionForLoanLossesExpensed
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=cof_LossSharingAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |