CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 7	$ 121	$ (1,276)	$ 230
Net change in unrealized gains (losses), net of tax:
Investment securities	110	220	868	399
Fair value option liabilities attributable to our own credit spread	(261)	7	146	(104)
Derivatives designated as cash flow hedges	3	5	93	19
Pension and post-retirement benefit plans	0	0	0	(3)
Total other comprehensive income (loss)	(148)	232	1,107	311
Comprehensive income (loss)	$ (141)	$ 353	$ (169)	$ 541