Chapter 11 Proceedings Chapter 11 Proceedings (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Plan of Reorganization [Abstract]
Equity Method Investment, Ownership Percentage		100.00%
Plan or Reorganization, Percentage of Common Stock lenders to receive		96.00%
Plan of Reorganization, Percentage of Common Stock existing equity holders to retain		4.00%
Plan or Reorganization, warrants existing equity holders		30.00%
Plan of Reogranization, percentage of common stock lenders to receive net of backstop fee		88.50%
Plan of Reorganization, backstop fee		7.50%
Substantial Stockholder percentage		4.99%
Debtor-in-Possession Financing [Abstract]
Debtor-in-Possession Financing, Amount Arranged		$ 75,000
Debtor-in-Possession Financing, Amount Currently Available		30,000
Debtor-in-Possession Financing, Unused Borrowings		45,000
Liabilities Subject to Compromise [Abstract]
Liabilities Subject to Compromise, Accounts Payable and Accrued Liabilities		55,587
Liabilities Subject to Compromise, Accrued Capital Costs		7,225
Liabilities Subject to Compromise, Undistributed Oil and Gas Revenues		11,989
Liabilities Subject to Compromise, Debt and Accrued Interest		905,629
Liabilities Subject to Compromise, Other Liabilities		3,958
Liabilities Subject to Compromise		984,388	$ 0
Reorganization Items [Abstract]
Reorganization items		6,565	$ 0	$ 0
Senior Notes [Member]
Reorganization Items [Abstract]
Debtor Reorganization Items, write-off of Deferred Financing Costs and Debt Discounts		8,662
Senior Notes [Member] | Debt Discount on Senior Notes Due 2020 [Member]
Reorganization Items [Abstract]
Debtor Reorganization Items, write-off of Deferred Financing Costs and Debt Discounts		1,864
Senior Notes [Member] | Senior Notes Due 2022 [Member]
Liabilities Subject to Compromise [Abstract]
Liabilities Subject to Compromise, Debt and Accrued Interest	[1]	400,000
Reorganization Items [Abstract]
Debtor Reorganization Items, write-off of Deferred Financing Costs and Debt Discounts		5,300
Debtor Reorganization Items, write-off of Debt Premiums		$ (3,961)

[1] Amounts are shown net of any debt discount or premium