Name:	cof_ContinuingInvolvementwithContinuedtobeRecognizedTransferredFinancialAssetsCashBalanceinSpreadandReserveAccounts
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Continuing Involvement with Continued to be Recognized Transferred Financial Assets, Liabilities Incurred

No definition available.

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Continuing Involvement with Derecognized Transferred Financial Assets, Cash Balance of Reserve or Spread Accounts

No definition available.

Name:	cof_ContinuingInvolvementwithDerecognizedTransferredFinancialAssetsCashBalanceofReserveorSpreadAccounts
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Continuing Involvement with Derecognized Transferred Financial Assets, Liabilities Incurred

No definition available.

Name:	cof_ContinuingInvolvementwithDerecognizedTransferredFinancialAssetsLiabilitiesIncurred
Namespace Prefix:	cof_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that have been derecognized. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719

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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.

No definition available.

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Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that continue to be recognized in the statement of financial position. Includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719