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Commitments (Details) MMBTU / d in Thousands |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Apr. 29, 2015 USD ($) shares | Mar. 13, 2015 | Apr. 22, 2014 | Nov. 02, 2012 | Mar. 11, 1997 USD ($) well | Dec. 31, 2015 USD ($) MMBTU / d well | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($)
Commitments [Line Items] |  |  |  |  |  |  |  |
Plugging And Abandonment Escrow Account |  |  |  |  |  | $ 3,089,000 | $ 3,097,000 |
Maximum annual contributions per employee (401K Plan) |  |  |  |  |  | 100.00% |  |
Cost recognized on defined contribution plan |  |  |  |  |  | $ 1,400,000 | $ 800,000 | $ 600,000
Employment Agreement, Term |  |  |  |  |  | 3 years |  |
Employment Agreement, Subsequent Extension |  |  |  | 1 year |  |  |  |
Employment Agreement, Notice Period Allowed For Termination |  |  |  | 90 days |  |  |  |
Other Commitment |  |  |  |  |  | $ 144,210,000 |  |
Purchase Commitment, Total | MMBTU / d |  |  |  |  |  | 1,452 |  |
Muskie Proppant LLC |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Accrued damages for non-utilization of supply contract obligations |  |  |  |  |  | $ 300,000 |  |
Chief Executive Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Other Commitment |  |  |  |  |  | 400,000 |  |
Employment Agreement, Annual Compensation | $ 460,000 |  |  |  |  |  |  |
Chief Operating Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Employment Agreement, Term |  | 2 years |  |  |  |  |  |
Chief Financial Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Employment Agreement, Term |  | 3 years | 3 years |  |  |  |  |
Management |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Other Commitment |  |  |  |  |  | $ 1,200,000 |  |
Minimum |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Minimum matching employer contribution for 401K |  |  |  |  |  | 3.00% |  |
Operating lease term (exceeding one year) |  |  |  |  |  | 1 year |  |
WCBB |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Purchasing Remaining Percent Interest In Oil And Gas Property |  |  |  |  | 50.00% |  |  |
Payments Held For Restricted Cash |  |  |  |  | $ 18,000 |  |  |
Significant Plugging Commitment Minimum Number Of Wells To Be Plugged | well |  |  |  |  | 20 |  |  |
Tenure Of Minimum Wells To Be Plugged |  |  |  |  | 20 years |  |  |
Number Of Wells Plugged | well |  |  |  |  |  | 463 |  |
Restricted Stock | Chief Executive Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Employment Agreement, Annual Grant of Shares | shares | 40,000 |  |  |  |  |  |  |
Restricted Stock | Chief Executive Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Employment Agreement, Maximum Annual Salary Granted in Options, Percent | 500.00% |  |  |  |  |  |  |

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