LONG-TERM LIABILITIES (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended	6 Months Ended
	Aug. 01, 2017	May. 22, 2015	Jun. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Aug. 11, 2014
LONG-TERM LIABILITIES
Derivative Financial Instruments			$ 469	$ 469
Convertible Debentures			1,636	1,636	$ 1,636
Senior Notes			230,410	230,410	300,000
Discount on Senior Notes			(2,824)	(2,824)	(3,947)
Contingent Earn-Out			6,800	6,800	6,530
Asset retirement obligations			30,751	30,751	29,771
Total long-term liabilities			486,907	486,907	468,739
Less current portion			789	789	381
Long-term portion			486,118	486,118	468,358
Long-term liabilities
Gain on retirement of debt			14,407	14,407
Credit Facility | The "Credit Facility"
Long-term liabilities
Line of Credit					$ 134,749
Credit Facility | The "First Lien Credit Facility"
Long-term liabilities
Line of Credit			$ 219,665	$ 219,665
Term of credit facility		5 years
Borrowing capacity		$ 250,000
Credit Facility | Certain Lenders | The "First Lien Credit Facility"
Long-term liabilities
Borrowing capacity		172,500
Additional borrowing capacity		30,000
Amount of First Lien Credit Facility exchanged from Senior Notes		45,230
Secured Convertible Debentures
Long-term liabilities
Percentage of principal amount at which debentures may be converted from the date of issuance until maturity into common stock			100.00%
Conversion price (in dollars per share)			$ 50	$ 50
Amount of bond redemptions			$ 0	$ 0
Secured Convertible Debentures | Maximum
Long-term liabilities
Percentage of issued and outstanding debentures may be converted each year			10.00%
Senior Notes
Long-term liabilities
Accrued unpaid interest rolled into the First Lien Term Loans		1,930
Percentage on initial purchase price						98.617%
Interest rate (as a percent)			9.00%	9.00%
Gain on retirement of debt				$ 14,400
Senior notes, face amount			$ 230,410	230,410
Senior note, market value			$ 110,600	$ 110,600
Senior Notes | Certain Lenders
Long-term liabilities
Face Value of Senior Notes exchanged to First Lien Credit Facility		$ 69,590
Senior Notes | Maximum | Forecast | Subsequent Event
Long-term liabilities
Percentage of Senior Notes can be redeemed on or after August 1, 2017	35.00%