FAIR VALUE OF FINANCIAL INSTRUMENTS - Carrying Value (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Senior Notes
Fair Value Of Instruments [Line Items]
Carrying value of debt	$ 218,453	$ 218,269
Fair value of debt	230,468	227,000
Finance Method Lease Obligations
Fair Value Of Instruments [Line Items]
Carrying value of debt	0	0
Letter of credit
Fair Value Of Instruments [Line Items]
Carrying value of debt	670	670
Revolver, due November 23, 2016 [Member]
Fair Value Of Instruments [Line Items]
Carrying value of debt	17,000	26,000
Fair value of debt	17,000	26,000
Term Loan B [Member]
Fair Value Of Instruments [Line Items]
Carrying value of debt	230,000	242,750
Fair value of debt	230,288	242,447
Other Debt [Member]
Fair Value Of Instruments [Line Items]
Carrying value of debt	$ 94	$ 0