DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS - Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jan. 04, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liability for private warrants	$ 12,850		$ 12,850			$ 0
Gain on fair value of private warrant liability	6,042	$ 0	17,989	$ 0
Carrying Amount | Fair Value, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	20,407		20,407			2,989
Borrowings from partner bank						21,000
Liability for private warrants	12,850		12,850
Estimated Fair Value | Fair Value, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	20,407		20,407			2,989
Borrowings from partner bank						21,000
Liability for private warrants	12,850		12,850		$ 30,800
Estimated Fair Value | Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	20,407		20,407			2,989
Borrowings from partner bank						0
Liability for private warrants	0		0
Estimated Fair Value | Fair Value, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0		0			0
Borrowings from partner bank						21,000
Liability for private warrants	0		0
Estimated Fair Value | Fair Value, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0		0			0
Borrowings from partner bank						$ 0
Liability for private warrants	$ 12,850		$ 12,850