LONG-TERM DEBT (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Borrowings [Abstract]
Less: current portion	$ (3,414)	$ (3,407)
Long-term debt less current maturities	236,591	236,979
Unamortized debt issuance costs	$ 7,900	$ 8,300
Promissory note payable
Borrowings [Abstract]
Interest rate	2.90%	2.90%
Carrying Value
Borrowings [Abstract]
Total long-term debt	$ 247,866	$ 248,716
Less: current portion	(3,414)	(3,407)
Long-term debt less current maturities	244,452	245,309
Carrying Value \| ABL Revolver
Borrowings [Abstract]
Total long-term debt	0	0
Carrying Value \| Term Loan B
Borrowings [Abstract]
Total long-term debt	246,250	246,875
Carrying Value \| Promissory note payable
Borrowings [Abstract]
Total long-term debt	1,616	1,841
Fair Value
Borrowings [Abstract]
Total long-term debt	251,560	247,790
Less: current portion	(3,451)	(3,398)
Long-term debt less current maturities	248,109	244,392
Fair Value \| ABL Revolver
Borrowings [Abstract]
Total long-term debt	0	0
Fair Value \| Term Loan B
Borrowings [Abstract]
Total long-term debt	249,944	245,949
Fair Value \| Promissory note payable
Borrowings [Abstract]
Total long-term debt	$ 1,616	$ 1,841

Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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