Securities (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Securities available for sale
Amortized Cost	$ 12,742	$ 14,470
Gross Unrealized Gains	161	57
Gross Unrealized Losses	57	183
Fair Value	12,846	14,344
U.S. Treasury
Securities available for sale
Amortized Cost	155	596
Gross Unrealized Gains	4	1
Gross Unrealized Losses	0	3
Fair Value	159	594
Residential mortgage-backed securities, U.S. government agency and government-sponsored agencies
Securities available for sale
Amortized Cost	6,009	7,298
Gross Unrealized Gains	47	1
Gross Unrealized Losses	4	98
Fair Value	6,052	7,201
Residential mortgage-backed securities, Privately issued
Securities available for sale
Amortized Cost	245	150
Gross Unrealized Gains	3	2
Gross Unrealized Losses	0	1
Fair Value	248	151
Privately issued - commercial mortgage-backed securities
Securities available for sale
Amortized Cost	1,474	1,566
Gross Unrealized Gains	54	5
Gross Unrealized Losses	1	25
Fair Value	1,527	1,546
Collateralized loan obligations
Securities available for sale
Amortized Cost	3,267	3,266
Gross Unrealized Gains	1	1
Gross Unrealized Losses	30	34
Fair Value	3,238	3,233
Other Asset Liability Management Securities
Securities available for sale
Amortized Cost	7	7
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	7	7
Asset Liability Management securities
Securities available for sale
Amortized Cost	11,157	12,883
Gross Unrealized Gains	109	10
Gross Unrealized Losses	35	161
Fair Value	11,231	12,732
Other debt securities, Direct bank purchase bonds
Securities available for sale
Amortized Cost	1,547	1,549
Gross Unrealized Gains	50	45
Gross Unrealized Losses	22	22
Fair Value	1,575	1,572
Other debt securities, Other
Securities available for sale
Amortized Cost	32	32
Gross Unrealized Gains	1	0
Gross Unrealized Losses	0	0
Fair Value	33	32
Equity securities
Securities available for sale
Amortized Cost	6	6
Gross Unrealized Gains	1	2
Gross Unrealized Losses	0	0
Fair Value	$ 7	$ 8

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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