CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS - USD ($) $ in Thousands		1 Months Ended	2 Months Ended	3 Months Ended		10 Months Ended
	Feb. 28, 2017	Mar. 31, 2017	Feb. 28, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Cash flows from operating activities:
Net income (loss)		$ (259,613)		$ 18,308		$ (247,639)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion and amortization		15,847		21,333
Write-down of oil and gas properties		256,435		0
Accretion expense		2,901		4,287
Gain on sale of oil and gas properties		0		0
Settlement of asset retirement obligations		(17,600)		(20,734)
Non-cash stock compensation expense		17		348
Non-cash derivative (income) expense		(2,484)		6,119
Non-cash interest expense		0		1
Non-cash reorganization items		0		0
Other non-cash expense		0		22
Change in current income taxes		0		20,049
Decrease in accounts receivable		6,728		2,144
(Increase) decrease in other current assets		964		237
Increase (decrease) in accounts payable		3,015		(13,701)
Increase (decrease) in other current liabilities		1,672		(5,534)
Investment in derivative contracts		(2,140)		0
Other		4,904		(393)
Net cash provided by (used in) operating activities		10,646		32,486
Cash flows from investing activities:
Investment in oil and gas properties		(5,584)		(37,081)
Proceeds from sale of oil and gas properties, net of expenses	$ 512,472	10,770		320
Investment in fixed and other assets		(2)		0
Net cash provided by (used in) investing activities		5,184		(36,761)
Cash flows from financing activities:
Repayments of bank borrowings	(341,500)	0		0
Repayments of building loan		(36)		(105)
Cash payment to noteholders		0		0
Debt issuance costs		0		0
Net payments for share-based compensation		0		(15)
Net cash used in financing activities		(36)		(120)
Net change in cash, cash equivalents and restricted cash		15,794		(4,395)
Cash, cash equivalents and restricted cash, beginning of period		238,513		282,237		238,513
Cash, cash equivalents and restricted cash, end of period	238,513	254,307	$ 238,513	$ 277,842	$ 254,307	282,237
Predecessor
Cash flows from operating activities:
Net income (loss)			630,317
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion and amortization			37,429
Write-down of oil and gas properties			0
Accretion expense			5,447
Gain on sale of oil and gas properties			(213,453)
Settlement of asset retirement obligations			(3,641)
Non-cash stock compensation expense			2,645
Non-cash derivative (income) expense			1,778
Non-cash interest expense			0
Non-cash reorganization items			(458,677)
Other non-cash expense			172
Change in current income taxes			3,570
Decrease in accounts receivable			6,354
(Increase) decrease in other current assets			(2,274)
Increase (decrease) in accounts payable			(4,652)
Increase (decrease) in other current liabilities			(9,653)
Investment in derivative contracts			(3,736)
Other			2,490
Net cash provided by (used in) operating activities			(5,884)
Cash flows from investing activities:
Investment in oil and gas properties			(8,754)
Proceeds from sale of oil and gas properties, net of expenses			505,383
Investment in fixed and other assets			(61)
Net cash provided by (used in) investing activities			496,568
Cash flows from financing activities:
Repayments of bank borrowings			(341,500)
Repayments of building loan			(24)
Cash payment to noteholders			(100,000)
Debt issuance costs			(1,055)
Net payments for share-based compensation			(173)
Net cash used in financing activities			(442,752)
Net change in cash, cash equivalents and restricted cash			47,932
Cash, cash equivalents and restricted cash, beginning of period		$ 238,513	190,581		$ 190,581	$ 238,513
Cash, cash equivalents and restricted cash, end of period	$ 238,513		$ 238,513