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Commitments - Narrative (Details) MMBTU / d in Thousands, $ in Thousands |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Nov. 02, 2016 shares | Mar. 13, 2015 | Apr. 22, 2014 | Nov. 01, 2012 | Mar. 11, 1997 USD ($) well | Dec. 31, 2016 USD ($) MMBTU / d well | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Commitments [Line Items] |  |  |  |  |  |  |  |
Plugging and abandonment escrow account on the WCBB properties (Note 15) |  |  |  |  |  | $ 3,100 |  |
Maximum annual contributions per employee (401K Plan) |  |  |  |  |  | 100.00% |  |
Cost recognized on defined contribution plan |  |  |  |  |  | $ 1,700 | $ 1,400 | $ 800
Purchase commitment daily volume | MMBTU / d |  |  |  |  |  | 1,379 |  |
Chief Executive Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Employment agreement term |  |  | 3 years |  |  |  |  |
Chief Operating Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Employment agreement term |  | 2 years |  |  |  |  |  |
Post employment benefits, eligibility term | 18 months |  |  |  |  |  |  |
Chief Financial Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Employment agreement term |  | 3 years |  |  |  |  |  |
Management |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Employment agreement term |  |  |  | 3 years |  |  |  |
Period of employment automatic extension |  |  |  | 1 year |  |  |  |
Employment agreement, notice period allowed for termination |  |  |  | 90 days |  |  |  |
Minimum |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Minimum matching employer contribution for 401K |  |  |  |  |  | 3.00% |  |
Operating lease term (exceeding one year) |  |  |  |  |  | 1 year |  |
WCBB |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Remaining percent interest in properties |  |  |  |  | 50.00% |  |  |
Monthly payments to abandonment trust obligation |  |  |  |  | $ 18 |  |  |
Plugging commitment, minimum number of wells to be plugged | well |  |  |  |  | 20 |  |  |
Period of well plugging commitment |  |  |  |  | 20 years |  |  |
Number of wells plugged to date | well |  |  |  |  |  | 513 |  |
Restricted stock | Chief Operating Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Annual employee compensation commitment, shares awarded (shares) | shares | 3,000 |  |  |  |  |  |  |
Restricted Stock Units (RSUs) | Chief Operating Officer |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Annual employee compensation commitment, shares awarded (shares) | shares | 14,820 |  |  |  |  |  |  |
Salary commitment under employment agreements | Management |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Other liabilities |  |  |  |  |  | $ 400 |  |
Transportation commitment |  |  |  |  |  |  |  |
Commitments [Line Items] |  |  |  |  |  |  |  |
Other liabilities |  |  |  |  |  | $ 3,820,181 |  |

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