LONG-TERM OBLIGATIONS - Summary of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Principal amount	$ 245,700	$ 10,900
Deferred debt issuance costs	(3,500)	(3,500)
Long-term obligations, including current portion	242,200	7,400
Current portion of long-term obligations	(9,927)	(1,612)
Long-term obligations, less current portion	232,256	5,775
Term Loan [Member] \| One Hundred Seventy Five Million Term Loan Facility [Member]
Debt Instrument [Line Items]
Principal amount	171,700	0
Revolving Credit Facility [Member] \| Five Hundred Fifty Million Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Principal amount	70,000	7,500
Promissory Notes [Member]
Debt Instrument [Line Items]
Principal amount	600	1,100
Finance Lease [Member]
Debt Instrument [Line Items]
Principal amount	$ 3,400	$ 2,300

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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