Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 6,437	$ 4,492	$ 3,237
OCI, net of tax:
Net change in net pension and postretirement costs	789	247	42
Net change in cash flow hedges	55	37	(70)
Net change in AFS securities	(3,164)	1,274	880
Other, net	0	2	19
Total OCI, net of tax	(2,320)	1,560	871
Total comprehensive income	4,117	6,052	4,108
Income Tax Effect of Items Included in OCI:
Net change in net pension and postretirement costs	243	79	11
Net change in cash flow hedges	17	11	(21)
Net change in AFS securities	(971)	396	271
Other, net	0	0	5
Total income taxes related to OCI	$ (711)	$ 486	$ 266