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	$ 2,319	$ 1,057	$ 1,791
Other comprehensive income (loss):
Net unrealized derivative instruments gains (losses) arising during the periods, net of income taxes of $(17), $33 and $35, respectively	(49)	97	103
Reclassification adjustment for net derivative (gains) losses included in net income, net of income taxes of ($34), ($38) and $14, respectively	(101)	(111)	43
Net unrealized debt securities gains (losses) arising during the periods, net of income taxes of $(172), $124 and $165, respectively	(528)	382	501
Reclassification of net debt securities (gains) losses to net income, net of income taxes of ($2), ($1) and ($8), respectively	(8)	(3)	(15)
Employee benefit plans:
Actuarial gain (loss), net of income taxes of $19, $(10) and $12, respectively	55	(27)	36
Reclassification of actuarial loss to net income, net of income taxes of $7, $4 and $6, respectively	26	13	13
Amortization of prior service cost, net of income taxes of $0, $0 and $0, respectively	0	0	(1)
Total other comprehensive income (loss), net of income taxes	(605)	351	680
Total comprehensive income (loss)	$ 1,714	$ 1,408	$ 2,471