Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 1,345	$ 1,532	$ 2,860	$ 2,948
OCI, net of tax:
Net change in net pension and postretirement costs	8	5	(6)	13
Net change in cash flow hedges	(317)	49	(192)	54
Net change in AFS securities	(550)	(2,849)	303	(7,838)
Net change in HTM securities	65	92	120	136
Other, net	1	(2)	2	(1)
Total OCI, net of tax	(793)	(2,705)	227	(7,636)
Total OCI	552	(1,173)	3,087	(4,688)
Income Tax Effect of Items Included in OCI:
Net change in net pension and postretirement costs	3	3	0	5
Net change in cash flow hedges	(97)	15	(59)	16
Net change in AFS securities	(187)	(867)	75	(2,380)
Net change in HTM securities	17	27	32	40
Total income taxes related to OCI	$ (264)	$ (822)	$ 48	$ (2,319)