FRESH START ACCOUNTING - Reorganization Adjustments (Details) - USD ($) $ in Thousands		10 Months Ended
	Feb. 28, 2017	Dec. 31, 2017
Reorganizations [Abstract]
Net consideration received for sale of Appalachia Properties	$ 512,472	$ 20,633
Cash transferred to restricted account	75,547
Break-up fee to Tug Hill	10,800
Repayment of outstanding borrowings under Pre-Emergence Credit Agreement	341,500	0
Repayment of 2017 Convertible Notes and 2022 Notes	100,000
Other fees and expenses	20,230
Total uses	548,077
Net change in cash and cash equivalents	$ (35,605)	$ 100,529