REORGANIZATION (Details) $ / shares in Units, a in Thousands					1 Months Ended	2 Months Ended	3 Months Ended
	Mar. 01, 2017 $ / shares shares	Feb. 28, 2017 USD ($) shares	Feb. 27, 2017 USD ($) shares	Dec. 09, 2016 a	Mar. 31, 2017 USD ($) shares	Feb. 28, 2017 USD ($) shares	Mar. 31, 2018 USD ($) shares
Restructuring Cost and Reserve [Line Items]
Net consideration received for sale of Appalachia Properties | $		$ 512,472,000			$ 10,770,000		$ 320,000
New shares issued in reorganization (in shares) | shares		20,000,000					682
7 ½% Senior Second Lien Notes due 2022 | Senior Notes
Restructuring Cost and Reserve [Line Items]
Interest rate							7.50%
Predecessor
Restructuring Cost and Reserve [Line Items]
Net consideration received for sale of Appalachia Properties | $						$ 505,383,000
New shares issued in reorganization (in shares) | shares					0	47,390
Predecessor | 1 ¾% Senior Convertible Notes due 2017
Restructuring Cost and Reserve [Line Items]
Interest rate			1.75%
Predecessor | 7 ½% Senior Second Lien Notes due 2022 | Senior Notes
Restructuring Cost and Reserve [Line Items]
Interest rate			7.50%
RSA | Common Stock
Restructuring Cost and Reserve [Line Items]
New shares issued in reorganization (in shares) | shares	20,000,000
RSA | Predecessor
Restructuring Cost and Reserve [Line Items]
Acreage sold in agreement | a				86
RSA | EQT Production Company | Disposal Group, Disposed of by Sale | Predecessor
Restructuring Cost and Reserve [Line Items]
Net consideration received for sale of Appalachia Properties | $			$ 522,500,000
RSA | Tug Hill | Disposal Group, Disposed of by Sale | Predecessor
Restructuring Cost and Reserve [Line Items]
Loss on contract termination | $						$ 11,500,000
RSA | Noteholders
Restructuring Cost and Reserve [Line Items]
Pro rata share of net cash proceeds | $			$ 100,000,000
Percentage of common stock issued in reorganization			95.00%
RSA | Noteholders | 7 ½% Senior Second Lien Notes due 2022 | Senior Notes
Restructuring Cost and Reserve [Line Items]
Aggregate principal amount of senior subordinated notes | $			$ 225,000,000
RSA | Noteholders | Common Stock
Restructuring Cost and Reserve [Line Items]
New shares issued in reorganization (in shares) | shares			19,000,000
RSA | Predecessor Company's Common Stockholders
Restructuring Cost and Reserve [Line Items]
Percentage of common stock issued in reorganization			5.00%
RSA | Predecessor Company's Common Stockholders | Common Stock
Restructuring Cost and Reserve [Line Items]
New shares issued in reorganization (in shares) | shares	1,000,000
Warrants issued in reorganization (in shares) | shares	3,500,000
Exercise price of warrants or rights (in usd per share) | $ / shares	$ 42.04
Exercise period for warrants	4 years