Derivative Instruments and Hedging Activities - Offsetting Liabilities (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Derivatives liabilities
Gross Amounts	$ 276	$ 710
Offsetting Amounts	0	0
Net Amounts as Recognized	276us-gaap_DerivativeLiabilities	710us-gaap_DerivativeLiabilities
Offsetting Amounts Not Netted, Financial Instruments	(161)	(262)
Offsetting Amounts Not Netted, Collateral pledged	(76)	(371)
Net Exposure	39	77
Repurchase agreements
Gross Amounts	869	907
Offsetting Amounts	0	0
Net Amounts as Recognized	869	907
Offsetting Amounts Note Netted, Financial Instruments	0cof_RepurchaseAgreementamountnotoffset	0cof_RepurchaseAgreementamountnotoffset
Offsetting Amounts Not Netted, Collateral Pledged	(869)	(907)
Net Exposure	$ 0	$ 0

Derivative, Collateral, Right To Claim Securities and Cash

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- Definition

Derivative Liability, Fair Value, Gross Asset Could Be Netted

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- Definition

Repurchase Agreement, amount not offset

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- Definition

Repurchase Agreement, amount offset in balance sheet

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Fair value, after effects of master netting arrangements, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities.

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount, after effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price offset against a right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Amount of right to receive securities collateral under master netting arrangements that have not been offset against securities sold under agreement to repurchase.

+ References

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Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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