CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) (UNAUDITED) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 88	$ 182	$ 482	$ 550
Net change in unrealized gains (losses), net of tax:
Investment securities	550	(346)	360	(205)
Fair value option liabilities attributable to our own credit spread	4	(8)	(37)	(9)
Derivatives designated as cash flow hedges	(107)	60	(43)	109
Pension and post-retirement benefit plans	(1)	(1)	(1)	(1)
Total other comprehensive income (loss)	446	(295)	279	(106)
Comprehensive income (loss)	$ 534	$ (113)	$ 761	$ 444