SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) obligation	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Revenue, Major Customer [Line Items]
Number of performance obligations | obligation			2
Basic vehicle warranty term			4 years
Revenue	$ 150,874,000	$ 97,336,000	$ 300,306,000	$ 155,011,000
Vehicle Sales With RVG
Revenue, Major Customer [Line Items]
Revenue	36,800,000	$ 0	55,500,000	$ 0
Vehicle Sales With OTA and Remarketing
Revenue, Major Customer [Line Items]
Deferred revenue	$ 21,700,000		$ 21,700,000		$ 15,400,000