LONG-TERM DEBT - Credit Facility Narrative (Details) $ in Thousands	Dec. 18, 2020 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Cash and cash equivalents		$ 18,355	$ 24,586
ABL Facility
Debt Instrument [Line Items]
Available borrowing capacity		$ 55,200
Term Loan
Debt Instrument [Line Items]
Line of Credit Facility, Accordion Feature, Increase Limit	$ 100,000
Principal amount, long-term debt issued	$ 250,000
Interest rate, original issue discount	0.03
Proceeds from Issuance of Debt	$ 242,500
Interest rate on convertible debt		11.95%
Standby Letters of Credit
Debt Instrument [Line Items]
Outstanding letters of credit		$ 24,500	$ 19,500
Letter of Credit | Line of Credit | ABL Facility
Debt Instrument [Line Items]
Borrowing capacity	150,000
Line of Credit Facility, Sublimit For Issuance	50,000
Line of Credit Facility, Sublimit for Swingline Borrowings	35,000
Line of Credit Facility, Accordion Feature, Increase Limit	$ 50,000