FAIR VALUE MEASUREMENTS AND DERIVATIVES - Significant Assumptions used to Determine Fair Value of Sponsor Warrants (Details) - Fair Value, Inputs, Level 2 [Member] - Black-Sholes Model [Member] - Sponsor Warrants [Member]	Sep. 30, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Remaining life (in years)	2 years 5 months 19 days	3 years 2 months 19 days
Stock Price [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants, measurement input	9.97	10.14
Strike Price [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants, measurement input	11.50	11.50
Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants, measurement input	63.0	54.0
Interest Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants, measurement input	0.4	0.2
Dividend Yield [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Warrants, measurement input	0.0	0.0