Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets
Gross Carrying Amount	$ 330	$ 331
Accumulated Amortization	(185)	(175)
Net Carrying Amount	145	156
Core deposit intangibles
Finite-Lived Intangible Assets
Gross Carrying Amount	229	229
Accumulated Amortization	(161)	(153)
Net Carrying Amount	68	76
Developed technology
Finite-Lived Intangible Assets
Gross Carrying Amount	62	62
Accumulated Amortization	(5)	(3)
Net Carrying Amount	57	59
Customer relationships
Finite-Lived Intangible Assets
Gross Carrying Amount	25	25
Accumulated Amortization	(8)	(7)
Net Carrying Amount	17	18
Operating leases
Finite-Lived Intangible Assets
Gross Carrying Amount	10	11
Accumulated Amortization	(8)	(9)
Net Carrying Amount	2	2
Other
Finite-Lived Intangible Assets
Gross Carrying Amount	4	4
Accumulated Amortization	(3)	(3)
Net Carrying Amount	$ 1	$ 1