DEBT - Summary of Cash Flow Hedges (Details) - Designated as Hedging Instrument - Interest rate swaps - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, gross asset	$ 614	$ 0
Cash flow hedge derivatives, gross liability	8,868	13,237
Other current assets
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, gross asset	0	0
Other non-current assets
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, gross asset	614	0
Other accrued liabilities
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, gross liability	4,778	4,774
Other long-term liabilities
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, gross liability	4,090	8,463
Accumulated other comprehensive loss, net of tax
Derivatives, Fair Value [Line Items]
Accumulated other comprehensive loss, interest rate swaps	(8,462)	(13,434)
Accumulated other comprehensive loss, interest rate swaps, tax provision	775	1,917
Accumulated other comprehensive loss, net of tax	$ (7,687)	$ (11,517)

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