Securities (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Securities available for sale
Amortized Cost	$ 14,356	$ 13,819
Gross Unrealized Gains	77	76
Gross Unrealized Losses	78	171
Fair Value	14,355	13,724
Residential mortgage-backed securities, U.S. government agency and government-sponsored agencies
Securities available for sale
Amortized Cost	7,879	7,649
Gross Unrealized Gains	8	2
Gross Unrealized Losses	27	91
Fair Value	7,860	7,560
Residential mortgage-backed securities, Privately issued
Securities available for sale
Amortized Cost	131	166
Gross Unrealized Gains	2	3
Gross Unrealized Losses	1	1
Fair Value	132	168
Privately issued - commercial mortgage-backed securities
Securities available for sale
Amortized Cost	1,586	1,689
Gross Unrealized Gains	15	15
Gross Unrealized Losses	6	13
Fair Value	1,595	1,691
Collateralized loan obligations
Securities available for sale
Amortized Cost	3,132	2,527
Gross Unrealized Gains	2	4
Gross Unrealized Losses	25	37
Fair Value	3,109	2,494
Other Asset Liability Management Securities
Securities available for sale
Amortized Cost	7	8
Gross Unrealized Gains	1	1
Gross Unrealized Losses	0	0
Fair Value	8	9
Asset Liability Management securities
Securities available for sale
Amortized Cost	12,735	12,039
Gross Unrealized Gains	28	25
Gross Unrealized Losses	59	142
Fair Value	12,704	11,922
Other debt securities, Direct bank purchase bonds
Securities available for sale
Amortized Cost	1,567	1,719
Gross Unrealized Gains	46	49
Gross Unrealized Losses	19	27
Fair Value	1,594	1,741
Other debt securities, Other
Securities available for sale
Amortized Cost	48	53
Gross Unrealized Gains	1	0
Gross Unrealized Losses	0	1
Fair Value	49	52
Equity securities
Securities available for sale
Amortized Cost	6	8
Gross Unrealized Gains	2	2
Gross Unrealized Losses	0	1
Fair Value	$ 8	$ 9

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

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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