CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 269	$ 204	$ 31	$ 500
Net change in unrealized gains (losses), net of tax:
Investment securities	(76)	110	(271)	217
Fair value option liabilities attributable to our own credit spread	129	(9)	141	(88)
Derivatives designated as cash flow hedges	10	(3)	12	(2)
Pension and post-retirement benefit plans	(1)	0	0	0
Total other comprehensive income (loss)	62	98	(118)	127
Comprehensive income (loss)	$ 331	$ 302	$ (87)	$ 627

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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