Investment Securities - Schedule Of Amortized Cost And Fair Value By Contractual Maturity (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
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	1,349
Total	1,349
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	1,175
Fair Value	1,175	$ 1,209
Amortized Cost
Within 1 year	14
After 1 year through 5 years	125
After 5 years through 10 years	399
After 10 years	1,466
Subtotal	2,004
Government agency issued MBS and CMO	7,872
Securities available for sale, amortized cost	9,876
Fair Value
Within 1 year	14
After 1 year through 5 years	119
After 5 years through 10 years	358
After 10 years	1,296
Subtotal	1,787
Government agency issued MBS and CMO	6,813
Securities available-for-sale	$ 8,600	$ 8,836