Investment Securities - Schedule Of Amortized Cost And Fair Value By Contractual Maturity (Details) - USD ($) $ in Millions	Jun. 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	687
Total	687
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	601
Fair Value	601	$ 705
Amortized Cost
Within 1 year	50
After 1 year through 5 years	122
After 5 years through 10 years	347
After 10 years	1,176
Subtotal	1,695
Government agency issued MBS and CMO	8,135
Securities available for sale, amortized cost	9,830
Fair Value
Within 1 year	50
After 1 year through 5 years	117
After 5 years through 10 years	319
After 10 years	1,050
Subtotal	1,536
Government agency issued MBS and CMO	7,405
Securities available-for-sale	$ 8,941	$ 8,707