LONG TERM DEBT (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Long-Term Debt
Total debt before unamortized discount and debt issuance costs	$ 525,975	$ 460,956
Unamortized discount	(10,428)	(10,692)
Total Debt	515,547	450,264
Less: Current portion of long-term debt	10,312	4,336
Long-term debt	505,235	445,928
Revolving Credit Facility | Prior Credit Agreement, dated June 17, 2013
Long-Term Debt
Total debt before unamortized discount and debt issuance costs		5,000
Term Loan B | Credit Agreement, dated March 6, 2018
Long-Term Debt
Total debt before unamortized discount and debt issuance costs	505,000
Term Loan B | Prior Credit Agreement, dated August 1, 2016
Long-Term Debt
Total debt before unamortized discount and debt issuance costs		280,000
Term Loan B | Prior Credit Agreement, dated June 17, 2013
Long-Term Debt
Total debt before unamortized discount and debt issuance costs		151,875
Seller notes
Long-Term Debt
Total debt before unamortized discount and debt issuance costs	4,163	5,912
Financing leases and other
Long-Term Debt
Total debt before unamortized discount and debt issuance costs	$ 16,812	$ 18,169