DEBT AND OTHER OBLIGATIONS (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
DEBT AND OTHER OBLIGATIONS
Total debt before unamortized discount and debt issuance costs	$ 508,564		$ 520,080
Unamortized discount and debt issuance costs, net	(9,264)		(9,407)
Total debt	499,300		510,673
Current portion of long-term debt	8,677	$ 7,964	8,583
Long-term debt	490,623	$ 489,597	502,090
Term Loan B
DEBT AND OTHER OBLIGATIONS
Total debt before unamortized discount and debt issuance costs	499,950		501,213
Current portion of long-term debt	5,050		5,050
Seller Notes
DEBT AND OTHER OBLIGATIONS
Total debt before unamortized discount and debt issuance costs	7,402		4,506
Current portion of long-term debt	3,288		2,513
Financing leases and other
DEBT AND OTHER OBLIGATIONS
Total debt before unamortized discount and debt issuance costs	1,212		14,361
Current portion of long-term debt	$ 339		$ 1,020

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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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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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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