Commitments and Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Rent expense	$ 37	$ 39	$ 38
Operating lease right-of-use asset obtained in exchange for lease obligations	3	$ 26	36
2022	28
2023	25
2024	25
2025	22
2026	21
Thereafter	44
Imputed interest	$ 21
Weighted-average discount rate	4.10%	4.20%
Weighted average remaining lease term	6 years 9 months 18 days	7 years 6 months
Payments for operating payments	$ 45	$ 49	$ 51
Estimate of possible loss	257
Loss contingency accrual	142
Indirect tax contingency	55
Other Liabilities
Loss Contingencies [Line Items]
Operating lease liabilities	144	164
Other Assets
Loss Contingencies [Line Items]
Operating lease right-of-use asset	$ 122	$ 141
Retail Finance Receivable \| Texas \| Geographic Concentration Risk
Loss Contingencies [Line Items]
Concentration risk (percent)	13.30%
Maximum \| Administrative Offices And Other
Loss Contingencies [Line Items]
Term of contract	11 years

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of loss contingency liability.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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