LONG-TERM DEBT - Maturities of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Maturities of long-term debt
2018 (remainder of year)	$ 2,897
2019	8,480
2020	7,329
2021	6,497
2022	6,098
Thereafter	490,394
Total debt before unamortized discount and debt issuance costs, net	521,695	$ 460,956
Unamortized discount and debt issuance costs, net	(9,702)
Total debt	$ 511,993	$ 450,264

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 payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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