CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 204	$ (21)	$ 500	$ 133
Net change in unrealized gains (losses), net of tax:
Investment securities	110	208	217	486
Fair value option liabilities attributable to credit spread	(9)	0	(88)	0
Derivatives designated as cash flow hedges	(3)	(11)	(2)	(56)
Total other comprehensive income	98	197	127	430
Comprehensive income	$ 302	$ 176	$ 627	$ 563

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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