Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 1,515	$ 1,416
OCI, net of tax:
Net change in net pension and postretirement costs	(14)	8
Net change in cash flow hedges	125	5
Net change in AFS securities	853	(4,989)
Net change in HTM securities	55	44
Other, net	1	1
Total OCI, net of tax	1,020	(4,931)
Total OCI	2,535	(3,515)
Income Tax Effect of Items Included in OCI:
Net change in net pension and postretirement costs	(3)	2
Net change in cash flow hedges	38	1
Net change in AFS securities	262	(1,513)
Net change in HTM securities	15	13
Total income taxes related to OCI	$ 312	$ (1,497)