SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) segment obligation	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Revenue, Major Customer [Line Items]
Number of operating segments | segment	1
Number of reportable segments | segment	1
Impairment Long Lived Asset Held For Use Statement of Income or Comprehensive Income Extensible Enumeration Not Disclosed Flag	impairment loss
Impairment of long-lived assets	$ 15,300	$ 0	$ 0
Number of performance obligations | obligation	2
Basic vehicle warranty term	4 years
Revenue	$ 595,271	608,181	27,111
Advertising expense	35,300	0	$ 0
Vehicle Sales With RVG
Revenue, Major Customer [Line Items]
Revenue	190,900	31,100
Vehicle Sales With OTA and Remarketing
Revenue, Major Customer [Line Items]
Deferred revenue	28,700	15,400
Vehicle Sales With OTA and Remarketing | Other current liabilities
Revenue, Major Customer [Line Items]
Deferred revenue	7,700	4,000
Vehicle Sales With OTA and Remarketing | Other Noncurrent Liabilities
Revenue, Major Customer [Line Items]
Deferred revenue	21,000	$ 11,400
Electric Vehicle Purchase Agreement
Revenue, Major Customer [Line Items]
Revenue	$ 43,700
Electric Vehicle Purchase Agreement | Customer Concentration Risk | Accounts Receivable | Government of Saudi Arabia
Revenue, Major Customer [Line Items]
Concentration risk (as a percent)	68.50%