Long-Term Debt (Details) $ in Thousands			4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 15, 2017 USD ($)	Apr. 19, 2017 USD ($)	Apr. 22, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)
Bankruptcy Proceedings
Plan of Reogranization, percentage of common stock lenders to receive net of backstop fee			88.50%
Debtor-in-Possession Financing [Abstract]
Debtor-in-Possession Financing, Amount Arranged			$ 75,000
New Credit Facility [Member] | Line of Credit [Member]
Bank Borrowings
Long-Term Debt, excluding current maturities				$ 198,000	$ 73,000
Line of Credit Facility, Maximum Borrowing Capacity		$ 600,000
Line of Credit, current borrowing base		330,000	320,000
Line of Credit, Letters of Credit Issuable		$ 25,000
Line of Credit Facility, Commitment Fee Percentage		0.50%
Line of Credit, Additional Interest Due to Payment Default		2.00%
Line of Credit, Required Security Interest on Oil and Gas Properties		85.00%
Line of Credit, Covenant, Debt to EBITDA Ratio, Minimum		4.0
Line of Credit, Covenant, Current Ratio, Minimum		1.0
New Credit Facility [Member] | Line of Credit [Member] | Minimum [Member] | Alternative Base Interest Rate [Member]
Bank Borrowings
Debt Instrument escalating basis spread on base rate		0.0175
Debt instrument escalating rates for eurodollar rate loans		0.0275
New Credit Facility [Member] | Line of Credit [Member] | Maximum [Member] | Alternative Base Interest Rate [Member]
Bank Borrowings
Debt Instrument escalating basis spread on base rate		0.0275
Debt instrument escalating rates for eurodollar rate loans		0.0375
Second Lien Notes [Member]
Bank Borrowings
Long-Term Debt, excluding current maturities	$ 198,000
Debt Instrument escalating basis spread on base rate	50
Additional interest in the event of default	0.020
Second Lien
Long-term Debt, Gross	$ 200,000
Debt Instrument, Unamortized Discount	(2,000)
Additional notes issuable	$ 100,000
Make whole premium during years 1 and 2	0.02
Make whole premium during year 3	0.02
Make whole premium during year 4	0.01
Second Lien, Required Security Interest on Proved Reserves	85.00%
Second Lien, Required Security Interest on Oil and Gas Properties	85.00%
Second Lien, Asset Coverage Ratio, Minimum	1.3
Second Lien, Covenant, Debt to EBITDA Ratio, Minimum	4.5
Second Lien Notes [Member] | Alternative Base Interest Rate [Member]
Bank Borrowings
Debt Instrument escalating basis spread on base rate	0.065
Second Lien Notes [Member] | London Interbank Offered Rate (LIBOR) [Member]
Bank Borrowings
Debt Instrument escalating basis spread on base rate	0.075
DIP Facility [Member]
Debtor-in-Possession Financing [Abstract]
Debtor-in-Possession Financing, Amount Arranged			$ 75,000
Debtor-in-Possession Financing, Fee on Unused Borrowings			3.00%
Successor [Member]
Bank Borrowings
Long-Term Debt, excluding current maturities				198,000	265,325
Interest expense including commitment fees and amortization of debt issuance costs relating to the credit facility				15,310	15,070
Write off of Deferred Debt Issuance Cost				0	2,676
Second Lien
Long-term Debt, Gross				198,000	273,000
Successor [Member] | Line of Credit [Member]
Bank Borrowings
Capitalized interest on our unproved properties				500	800
Successor [Member] | New Credit Facility [Member]
Bank Borrowings
Debt Issuance Costs, Net					(5,500)
Successor [Member] | New Credit Facility [Member] | Line of Credit [Member]
Bank Borrowings
Interest expense including commitment fees and amortization of debt issuance costs relating to the credit facility				15,300	14,900
Write off of Deferred Debt Issuance Cost					2,700
Commitment fees included in interest expense, net				200	400
Successor [Member] | Second Lien Notes [Member]
Bank Borrowings
Debt Issuance Costs, Net				0	(5,683)
Long-Term Debt, excluding current maturities				0	200,000
Interest expense including commitment fees and amortization of debt issuance costs relating to the credit facility					800
Second Lien
Debt Instrument, Unamortized Discount				$ 0	(1,992)
Long-term Debt					$ 192,300
Predecessor [Member]
Bank Borrowings
Interest expense including commitment fees and amortization of debt issuance costs relating to the credit facility			$ 13,347			$ 75,870
Write off of Deferred Debt Issuance Cost			0			0
Capitalized interest on our unproved properties			0			4,900
Predecessor [Member] | Senior Notes [Member]
Bank Borrowings
Interest expense including commitment fees and amortization of debt issuance costs relating to the credit facility			0			70,800
Contractual Interest Expense on Prepetition Liabilities Not Recognized in Statement of Operations			21,600
Predecessor [Member] | Line of Credit [Member]
Bank Borrowings
Interest expense including commitment fees and amortization of debt issuance costs relating to the credit facility			6,800			9,400
Commitment fees included in interest expense, net			0			$ 500
Predecessor [Member] | DIP Facility [Member]
Bank Borrowings
Interest expense including commitment fees and amortization of debt issuance costs relating to the credit facility			$ 6,400