XML 72 R61.htm IDEA: XBRL DOCUMENT
v3.21.1

Derivative Instruments and Hedging Activities - Hedged Items in Fair Value Hedging Relationship (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Hedged Assets, Fair Value Hedge, Cumulative Increase (Decrease) | $ (1) |
Hedged Assets, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 249 |
Prepayable Financial Asset Closed Portfolio, Last-of-Layer, Amortized Cost | 225 |
Available-for-sale securities |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount of Assets | 9,948 | $ 9,797
Hedged Assets, Fair Value Hedge, Cumulative Increase (Decrease) | 485 | 590
Hedged Assets, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 194 | 200
Interest-bearing deposits |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Of Liabilities | (10,820) | (11,312)
Hedged Liabilities, Fair Value Hedge, Cumulative Increase (Decrease) | (155) | (213)
Hedged Liabilities, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 0 | 0
Securitized debt obligations |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Of Liabilities | (7,536) | (7,609)
Hedged Liabilities, Fair Value Hedge, Cumulative Increase (Decrease) | (96) | (171)
Hedged Liabilities, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 15 | 20
Senior and subordinated notes |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Of Liabilities | (20,265) | (21,927)
Hedged Liabilities, Fair Value Hedge, Cumulative Increase (Decrease) | (913) | (1,282)
Hedged Liabilities, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | $ (633) | $ (666)

X
- Definition Carry amount of assets hedged in fair value hedging relationship + References No definition available. + Details
Name: | cof_CarryingAmountOfAssets
Namespace Prefix: | cof_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The carry amount of liabilities in fair value hedging relationship + References No definition available. + Details
Name: | cof_CarryingAmountOfLiabilities
Namespace Prefix: | cof_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition [Line Items] for Table shows the carrying amount and associated cumulative basis adjustment related to the application of hedge accounting that is included in the carrying amount of hedged assets and liabilities in fair value hedging relationships. + References No definition available. + Details
Name: | cof_HedgedItemsInFairValueHedgingRelationshipLineItems
Namespace Prefix: | cof_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959 + Details
Name: | us-gaap_HedgedAssetDiscontinuedFairValueHedgeCumulativeIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959 + Details
Name: | us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959 + Details
Name: | us-gaap_HedgedLiabilityDiscontinuedFairValueHedgeCumulativeIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959 + Details
Name: | us-gaap_HedgedLiabilityFairValueHedgeCumulativeIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amortized cost of closed portfolio of prepayable financial asset, used to designate hedging relationship in which hedged item is last layer expected to be remaining at end of hedging relationship. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EEE -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999718-113959 + Details
Name: | us-gaap_PrepayableFinancialAssetClosedPortfolioLastOfLayerAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_AvailableforsaleSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_InterestBearingDepositsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=cof_SecuritizedDebtObligationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=cof_SeniorAndSubordinatedNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |