Investment Securities - Schedule Of Amortized Cost And Fair Value By Contractual Maturity (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Amortized Cost
Within 1 year	$ 0
After 1 year through 5 years	0
After 5 years through 10 years	0
After 10 years	0
Subtotal	0
Government agency issued MBS and CMO	1,385
Total	1,385
Fair Value
Within 1 year	0
After 1 year through 5 years	0
After 5 years through 10 years	0
After 10 years	0
Subtotal	0
Government agency issued MBS and CMO	1,222
Fair Value	1,222	$ 705
Amortized Cost
Within 1 year	45
After 1 year through 5 years	117
After 5 years through 10 years	397
After 10 years	1,301
Subtotal	1,860
Government agency issued MBS and CMO	8,232
Securities available for sale, amortized cost	10,092
Fair Value
Within 1 year	45
After 1 year through 5 years	110
After 5 years through 10 years	351
After 10 years	1,107
Subtotal	1,613
Government agency issued MBS and CMO	7,105
Securities available-for-sale	$ 8,718	$ 8,707