Other Assets (Intangible Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	$ (95)	$ (78)
Total intangible assets, gross	207	207
Net intangible assets	112	129
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2022	15
2023	25
2024	18
2025	14
2026	14
Technology
Finite-Lived Intangible Assets [Line Items]
Gross intangible assets	122	122
Accumulated amortization	(45)	(36)
Net carrying value	77	86
Customer lists
Finite-Lived Intangible Assets [Line Items]
Gross intangible assets	58	58
Accumulated amortization	(47)	(42)
Net carrying value	11	16
Purchased credit card relationships
Finite-Lived Intangible Assets [Line Items]
Gross intangible assets	25	25
Accumulated amortization	(2)	0
Net carrying value	23	25
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross intangible assets	2	2
Accumulated amortization	(1)	0
Net carrying value	$ 1	$ 2