FINANCING ARRANGEMENTS AND LONG-TERM DEBT - Long-term Debt and Annual Maturities of Debt Obligations Tables (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
FINANCING ARRANGEMENTS AND LONG-TERM DEBT
Long-term debt, gross	$ 116,749	$ 125,300
Debt discount	(74)	(181)
Debt issuance costs	(2,338)	(3,077)
Long-term debt, net	114,337	122,031
Less current installments on long term debt	15,499	5,546
Long-term debt	98,838	116,485
Secured Debt
FINANCING ARRANGEMENTS AND LONG-TERM DEBT
Long-term debt, gross	109,500	118,000
Note payable
FINANCING ARRANGEMENTS AND LONG-TERM DEBT
Long-term debt, gross	7,038	7,078
Convertible Notes Payable
FINANCING ARRANGEMENTS AND LONG-TERM DEBT
Long-term debt, gross	$ 211	$ 211

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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