Fair Values (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Investment securities:
Equity securities	$ 42	$ 41
Debt securities	3,922
Derivatives, gross	307	521
Liabilities
Derivatives, gross	560	801
Fair Value, Recurring
Investment securities:
Equity securities	42	41
Debt securities	3,922	4,537
Derivatives, gross	307	521
Total Assets	4,271	5,099
Liabilities
Derivatives, gross	560	801
Total Liabilities	560	801
Level 1 | Fair Value, Recurring
Investment securities:
Equity securities	41	40
Debt securities	0	0
Derivatives, gross	0	0
Total Assets	41	40
Liabilities
Derivatives, gross	0	0
Total Liabilities	0	0
Level 2 | Fair Value, Recurring
Investment securities:
Equity securities	1	1
Debt securities	3,870	4,490
Derivatives, gross	284	494
Total Assets	4,155	4,985
Liabilities
Derivatives, gross	560	801
Total Liabilities	560	801
Level 3 | Fair Value, Recurring
Investment securities:
Equity securities	0	0
Debt securities	52	47
Derivatives, gross	23	27
Total Assets	75	74
Liabilities
Derivatives, gross	0	0
Total Liabilities	$ 0	$ 0