Discontinued Operations Discontinued Operations-Summary of Assets and Liabilities of Disposal Group Held for Sale (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012		Jun. 30, 2012	Dec. 31, 2011
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	$ 23		$ 200		$ 185	$ 103
Assets of discontinued operations	175		2,032
Liabilities of discontinued operations	229		1,501
Insurance business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	0		2
Interest bearing deposits with banks	0		29
Available-for-sale securities	0		1,411
Other assets	0		226
Assets of discontinued operations	0		1,668
Insurance policy and claim reserves	0		988
Other liabilities	0		224
Liabilities of discontinued operations	0		1,212
Card and Retail Services
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	22		197
Other assets	71		84
Assets of discontinued operations	93		281
Other liabilities	228	[1]	283	[1]
Liabilities of discontinued operations	$ 228		$ 283

[1] At June 30, 2013 and December 31, 2012, other liabilities primarily consists of amounts due to Capital One for cash collections we have received on customer accounts while we continue to service these accounts on an interim basis. Additionally at June 30, 2013 and December 31, 2012, other liabilities also includes $158 million and $59 million, respectively, with respect to enhancement services products as discussed above.