CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 177	$ 94	$ 208	$ 594
Net change in unrealized gains (losses), net of tax:
Investment securities	(137)	22	(408)	239
Fair value option liabilities attributable to our own credit spread	(47)	(45)	94	(133)
Derivatives designated as cash flow hedges	22	2	34	0
Total other comprehensive income (loss)	(162)	(21)	(280)	106
Comprehensive income (loss)	$ 15	$ 73	$ (72)	$ 700

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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