Fair Values (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Investment securities:
Equity securities	$ 42	$ 41
Debt securities	4,045
Derivatives, gross	205	521
Liabilities
Derivatives, gross	828	801
Fair Value, Recurring
Investment securities:
Equity securities	42	41
Debt securities	4,045	4,537
Derivatives, gross	205	521
Total Assets	4,292	5,099
Liabilities
Derivatives, gross	828	801
Total Liabilities	828	801
Level 1 | Fair Value, Recurring
Investment securities:
Equity securities	42	40
Debt securities	0	0
Derivatives, gross	0	0
Total Assets	42	40
Liabilities
Derivatives, gross	0	0
Total Liabilities	0	0
Level 2 | Fair Value, Recurring
Investment securities:
Equity securities	0	1
Debt securities	3,981	4,490
Derivatives, gross	178	494
Total Assets	4,159	4,985
Liabilities
Derivatives, gross	828	801
Total Liabilities	828	801
Level 3 | Fair Value, Recurring
Investment securities:
Equity securities	0	0
Debt securities	64	47
Derivatives, gross	27	27
Total Assets	91	74
Liabilities
Derivatives, gross	0	0
Total Liabilities	$ 0	$ 0