Securities (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Securities available for sale
Amortized Cost	$ 14,802	$ 16,194
Gross Unrealized Gains	78	76
Gross Unrealized Losses	210	453
Fair Value	14,670	15,817
U.S. government sponsored agencies
Securities available for sale
Amortized Cost		73
Fair Value		73
Residential mortgage-backed securities, U.S. government agency and government-sponsored agencies
Securities available for sale
Amortized Cost	8,281	9,194
Gross Unrealized Gains	3	2
Gross Unrealized Losses	127	296
Fair Value	8,157	8,900
Residential mortgage-backed securities, Privately issued
Securities available for sale
Amortized Cost	188	220
Gross Unrealized Gains	4	4
Gross Unrealized Losses	1	2
Fair Value	191	222
Privately issued - commercial mortgage-backed securities
Securities available for sale
Amortized Cost	1,824	1,947
Gross Unrealized Gains	14	8
Gross Unrealized Losses	25	85
Fair Value	1,813	1,870
Collateralized loan obligations
Securities available for sale
Amortized Cost	2,543	2,670
Gross Unrealized Gains	13	25
Gross Unrealized Losses	22	22
Fair Value	2,534	2,673
Asset-backed and other
Securities available for sale
Amortized Cost	18	34
Gross Unrealized Gains	1	1
Fair Value	19	35
Asset Liability Management securities
Securities available for sale
Amortized Cost	12,854	14,138
Gross Unrealized Gains	35	40
Gross Unrealized Losses	175	405
Fair Value	12,714	13,773
Other debt securities, Direct bank purchase bonds
Securities available for sale
Amortized Cost	1,888	1,968
Gross Unrealized Gains	42	35
Gross Unrealized Losses	33	43
Fair Value	1,897	1,960
Other debt securities, Other
Securities available for sale
Amortized Cost	54	81
Gross Unrealized Losses	2	5
Fair Value	52	76
Equity securities
Securities available for sale
Amortized Cost	6	7
Gross Unrealized Gains	1	1
Fair Value	$ 7	$ 8