CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income		$ 268	$ 293	$ 86
Available-for-sale securities:
Noncredit portion of OTTI reclassification (into) out of other comprehensive income (loss), net(1)	[1]	0	0	1
Unrealized gains (losses), net(2)	[2]	(84)	193	(261)
Reclassification into earnings, net(3)	[3]	(24)	(26)	(37)
Net change from available-for-sale securities		(108)	167	(297)
Cash flow hedging instruments:
Unrealized gains (losses), net(4)	[4]	(10)	(39)	67
Reclassification into earnings, net(5)	[5]	271	76	87
Net change from cash flow hedging instruments		261	37	154
Foreign currency translation gains (losses), net		(3)	0	0
Other comprehensive income (loss)		150	204	(143)
Comprehensive income (loss)		$ 418	$ 497	$ (57)

[1] Amount is net of benefit from income taxes of less than $1 million for the year ended December 31, 2013

[2] Amounts are net of benefit from income taxes of $52 million for the year ended December 31, 2015, net of provision for income taxes of $117 million for the year ended December 31, 2014, and net of benefit from income taxes of $156 million for the year ended December 31, 2013.

[3] Amounts are net of provision for income taxes of $15 million, $16 million and $23 million for the years ended December 31, 2015, 2014 and 2013, respectively.

[4] Amounts are net of benefit from income taxes of $7 million and $29 million for the years ended December 31, 2015 and 2014, respectively, and net of provision for income taxes of $33 million for the year ended December, 2013.

[5] Amounts are net of benefit from income taxes of $168 million, $49 million and $52 million for the years ended December 31, 2015, 2014 and 2013, respectively.