Summary of Property and Equipment (Detail) $ in Thousands	4 Months Ended	8 Months Ended
	Dec. 31, 2016 USD ($) $ / bbl	Sep. 12, 2016 USD ($) $ / bbl	Dec. 31, 2015 USD ($) $ / bbl	Dec. 31, 2014 $ / bbl
Property, Plant and Equipment [Line Items]
Proved Oil and Gas Property, Full Cost Method	$ 251,083
Undeveloped Leasehold Costs Transferred	$ 3,800
Capitalized Costs, Proved Properties		$ 500
Interest Costs Capitalized		$ 100
Amortization Expense Per Physical Unit of Production | $ / bbl	11.20	10.04	42.22	37.85
Oil and gas properties:
Proved			$ 2,678,415
Unproved Oil and Gas Property, Full Cost Method	$ 4,719
Unproved 1	4,700		6,881
Oil and Gas Property, Full Cost Method, Gross	255,802
Total oil and gas properties			2,685,296
Other property and equipment	3,575		31,365
Total property and equipment	259,377		2,716,661
Accumulated depreciation, depletion and amortization 1	(11,904)		(2,372,266)
Property and equipment, net (successful efforts method)	$ 247,473		$ 344,395