Oil and Gas Exploration and Production Industries Disclosures, Costs Incurred (Details) - USD ($) $ in Thousands |
12 Months Ended | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items] | |||||||||||||||||||
| Acquisition Costs of Properties - Unproved | $ 3,216,634 | [1] | $ 133,857 | $ 370,414 | |||||||||||||||
| Acquisition Costs of Properties - Proved | 749,023 | [2] | 480,617 | 139,101 | |||||||||||||||
| Subtotal | 3,965,657 | 614,474 | 509,515 | ||||||||||||||||
| Exploration Costs | 165,751 | 252,692 | 395,973 | ||||||||||||||||
| Development Costs | 2,313,876 | [3] | 4,061,117 | [4] | 6,999,281 | [5] | |||||||||||||
| Total | 6,445,284 | 4,928,283 | 7,904,769 | ||||||||||||||||
| United States | |||||||||||||||||||
| Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items] | |||||||||||||||||||
| Acquisition Costs of Properties - Unproved | 3,216,598 | [1] | 133,801 | 365,915 | |||||||||||||||
| Acquisition Costs of Properties - Proved | 749,023 | [2] | 480,617 | 138,772 | |||||||||||||||
| Subtotal | 3,965,621 | 614,418 | 504,687 | ||||||||||||||||
| Exploration Costs | 156,295 | 206,814 | 332,703 | ||||||||||||||||
| Development Costs | 2,252,713 | [3] | 3,847,813 | [4] | 6,638,192 | [5] | |||||||||||||
| Total | 6,374,629 | 4,669,045 | 7,475,582 | ||||||||||||||||
| Trinidad | |||||||||||||||||||
| Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items] | |||||||||||||||||||
| Acquisition Costs of Properties - Unproved | 0 | [1] | 0 | 0 | |||||||||||||||
| Acquisition Costs of Properties - Proved | 0 | [2] | 0 | 0 | |||||||||||||||
| Subtotal | 0 | 0 | 0 | ||||||||||||||||
| Exploration Costs | 2,695 | 22,837 | 2,794 | ||||||||||||||||
| Development Costs | 72,147 | [3] | 102,715 | [4] | 89,555 | [5] | |||||||||||||
| Total | 74,842 | 125,552 | 92,349 | ||||||||||||||||
| Other International | |||||||||||||||||||
| Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items] | |||||||||||||||||||
| Acquisition Costs of Properties - Unproved | [6] | 36 | [1] | 56 | 4,499 | ||||||||||||||
| Acquisition Costs of Properties - Proved | [6] | 0 | [2] | 0 | 329 | ||||||||||||||
| Subtotal | [6] | 36 | 56 | 4,828 | |||||||||||||||
| Exploration Costs | [6] | 6,761 | 23,041 | 60,476 | |||||||||||||||
| Development Costs | [6] | (10,984) | [3] | 110,589 | [4] | 271,534 | [5] | ||||||||||||
| Total | [6] | $ (4,187) | $ 133,686 | $ 336,838 | |||||||||||||||
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