CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 94	$ 33	$ 594	$ 166
Net change in unrealized gains (losses), net of tax:
Investment securities	22	(112)	239	374
Fair value option liabilities attributable to our own credit spread	(45)	0	(133)	0
Derivatives designated as cash flow hedges	2	9	0	(47)
Total other comprehensive income (loss)	(21)	(103)	106	327
Comprehensive income (loss)	$ 73	$ (70)	$ 700	$ 493

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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