CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (238)	$ 296
Net change in unrealized gains (losses), net of tax:
Investment securities	(195)	107
Fair value option liabilities attributable to our own credit spread	12	(79)
Derivatives designated as cash flow hedges	2	1
Pension and post-retirement benefit plans	1	0
Total other comprehensive income (loss)	(180)	29
Comprehensive income (loss)	$ (418)	$ 325

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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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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