Discontinued Operations Discontinued Operations-Summary of Assets and Liabilities of Disposal Group Held for Sale (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012		Sep. 30, 2012	Dec. 31, 2011
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	$ 24		$ 200		$ 174	$ 103
Assets of discontinued operations	200		2,032
Liabilities of discontinued operations	114		1,501
Insurance business [Member]
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 [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	23		197
Other assets	96	[1]	84	[1]
Assets of discontinued operations	119		281
Other liabilities	113	[2]	283	[2]
Liabilities of discontinued operations	$ 113		$ 283

[1] At September 30, 2013 and December 31, 2012, other assets primarily consists of current and deferred taxes.

[2] At September 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 as well as certain legal accruals as discussed above.