Discontinued Operations Discontinued Operations-Operating Results of Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations before income tax	$ (76)		$ 2,164		$ (195)		$ 2,721
Insurance business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net interest income and other revenues	(2)	[1]	(13)	[1]	70	[1]	64	[1]
Income (loss) from discontinued operations before income tax	(7)		(89)		6		(100)
Commercial Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net interest income and other revenues	7	[1]	1	[1]	8	[1]	22	[1]
Income (loss) from discontinued operations before income tax	3		0		4		20
Card and Retail Services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net interest income and other revenues	0	[1]	2,431	[1],[2]	0	[1]	3,356	[1],[2]
Income (loss) from discontinued operations before income tax	$ (72)	[3]	$ 2,253	[2]	$ (205)	[3]	$ 0	[2]

[1] Interest expense, which is included as a component of net interest income, was allocated to discontinued operations in accordance with our existing internal transfer pricing policy. This policy uses match funding based on the expected lives of the assets and liabilities of the business at the time of origination, subject to periodic review, as demonstrated by the expected cash flows and re-pricing characteristics of the underlying assets.

[2] For the six months ended June 30, 2012, amount includes a gain of $79 million resulting from the sale of account relationships to HSBC Bank USA which we had previously purchased from HSBC Bank USA in July 2004.

[3] For the six months ended June 30, 2013, amount includes an incremental expense of $100 million recorded based on additional information received relating to actions taken and to be taken in connection with an industry review of enhancement services products. We continue to review information relating to our enhancement services products. As additional information becomes available, further adjustments may be required. Additionally for the three and six months ended June 30, 2013, the amounts also reflect a legal accrual of $40 million as well as expenses related to activities to complete the separation of the credit card operational infrastructure between us and Capital One. We expect costs associated with the separation of the credit card operational infrastructure to continue through the remainder of 2013. See Note 16, "Litigation and Regulatory Matters," for further discussion of the legal accrual.