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Summary of Significant Accounting Policies - Narrative (Details) | 12 Months Ended |
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Dec. 31, 2016 USD ($) Mcf / bbl purchaser shares | Dec. 31, 2015 USD ($) shares | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Accounts receivable, collection period | 30 days |  |  |
Allowance for doubtful accounts | $ 0 | $ 0 |  |
Impairment of oil and gas properties | $ 715,495,000 | 1,440,418,000 | $ 0 |
Conversion ratio, gas to barrels of oil | Mcf / bbl | 6 |  |  |
Capitalized costs of oil and natural gas properties excluded from amortization | $ 1,580,305,000 | 1,817,701,000 |  | $ 575,521,000
Unrecognized tax benefits that would impact effective tax rate | 0 |  |  |
Interest and penalties associated with uncertain tax positions | 0 |  |  |
Oil and gas reclamation liability, noncurrent | $ 0 | $ 0 |  |
Investment owned, balance (in shares) | shares |  | 0 |  |
Investment in Diamondback Energy, Inc. |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Investment owned, balance (in shares) | shares | 0 |  |  |
Investment in Grizzly Oil Sands ULC |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Equity method investment recognized impairment charges | $ 23,100,000 | $ 101,600,000 |  |
Investment in Tatex Thailand III, LLC |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Equity method investment recognized impairment charges |  |  | $ 12,100,000 |
Minimum |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Useful life | 3 years |  |  |
Minimum | Restricted stock |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Vesting period | 2 years |  |  |
Maximum |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Useful life | 30 years |  |  |
Maximum | Restricted stock |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Vesting period | 5 years |  |  |
Customer concentration risk | Accounts receivable |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Concentration risk, number of purchasers | purchaser | 3 |  |  |

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