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Fair Value Measurements - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
Fair Value Measurements - Narrative (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairments		$ 0	$ 0	$ 1,900,000
Shift Technologies, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment loss		$ 1,700,000	$ 39,200,000
Franchise Rights
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Franchise value, impairment	$ 1,900,000