Fair Values (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Investment securities:
Equity securities	$ 55	$ 79
Debt securities	4,003
Derivatives, gross	423	590
Liabilities
Derivatives, gross	341	139
Fair Value, Recurring
Investment securities:
Equity securities	55	79
Debt securities	4,003	2,512
Derivatives, gross	423	590
Total Assets	4,481	3,181
Liabilities
Derivatives, gross	341	139
Total Liabilities	341	139
Level 1 | Fair Value, Recurring
Investment securities:
Equity securities	54	78
Debt securities	0	0
Derivatives, gross	0	0
Total Assets	54	78
Liabilities
Derivatives, gross	0	0
Total Liabilities	0	0
Level 2 | Fair Value, Recurring
Investment securities:
Equity securities	1	1
Debt securities	3,971	2,480
Derivatives, gross	423	590
Total Assets	4,395	3,071
Liabilities
Derivatives, gross	341	139
Total Liabilities	341	139
Level 3 | Fair Value, Recurring
Investment securities:
Equity securities	0	0
Debt securities	32	32
Derivatives, gross	0	0
Total Assets	32	32
Liabilities
Derivatives, gross	0	0
Total Liabilities	$ 0	$ 0