Business Segment Information (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2015 |
Mar. 31, 2015 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Schedule of Segment Reporting Information By Segment [Abstract] | |||||||||||||||||||||||
| Crude Oil and Condensate | $ 4,317,341 | $ 4,934,562 | $ 9,742,480 | ||||||||||||||||||||
| Natural Gas Liquids | 437,250 | 407,658 | 934,051 | ||||||||||||||||||||
| Natural Gas | 742,152 | 1,061,038 | 1,916,386 | ||||||||||||||||||||
| Gains (Losses) on Mark-to-Market Commodity Derivative Contracts | (99,608) | 61,924 | 834,273 | ||||||||||||||||||||
| Gathering, Processing and Marketing | 1,966,259 | 2,253,135 | 4,046,316 | ||||||||||||||||||||
| Gains (Losses) on Asset Dispositions, Net | 205,835 | (8,798) | 507,590 | ||||||||||||||||||||
| Other, Net | 81,403 | 47,909 | 54,244 | ||||||||||||||||||||
| Net Operating Revenues | $ 2,402,039 | $ 2,118,504 | $ 1,775,740 | $ 1,354,349 | $ 1,796,761 | $ 2,172,428 | $ 2,469,701 | $ 2,318,538 | 7,650,632 | [1] | 8,757,428 | [2] | 18,035,340 | [3] | |||||||||
| Depreciation, Depletion and Amortization | 3,553,417 | 3,313,644 | 3,997,041 | ||||||||||||||||||||
| Operating Income (Loss) | (105,487) | (193,480) | (288,173) | (638,141) | (329,753) | (6,222,957) | 39,626 | (172,995) | (1,225,281) | (6,686,079) | 5,241,823 | ||||||||||||
| Interest Income | 2,619 | 3,469 | 2,239 | ||||||||||||||||||||
| Other Income (Expense) | (53,162) | (1,553) | (47,289) | ||||||||||||||||||||
| Net Interest Expense | 281,681 | 237,393 | 201,458 | ||||||||||||||||||||
| Income (Loss) Before Income Taxes | (194,010) | (272,250) | (380,277) | (710,968) | (398,826) | (6,274,921) | (11,478) | (236,331) | (1,557,505) | (6,921,556) | 4,995,315 | ||||||||||||
| Income Tax Provision (Benefit) | (51,658) | $ (82,250) | $ (87,719) | $ (239,192) | (114,530) | $ (2,199,182) | $ (16,746) | $ (66,583) | (460,819) | (2,397,041) | 2,079,828 | ||||||||||||
| Additions to Oil and Gas Properties, Excluding Dry Hole Costs | 6,329,369 | 4,710,404 | 7,471,177 | ||||||||||||||||||||
| Total Property, Plant and Equipment, Net | 25,707,078 | 24,210,721 | 25,707,078 | 24,210,721 | 29,172,644 | ||||||||||||||||||
| Total Assets | 29,459,433 | 26,970,470 | 29,459,433 | 26,970,470 | 34,758,599 | ||||||||||||||||||
| United States | |||||||||||||||||||||||
| Schedule of Segment Reporting Information By Segment [Abstract] | |||||||||||||||||||||||
| Crude Oil and Condensate | 4,265,036 | 4,917,731 | 9,526,149 | ||||||||||||||||||||
| Natural Gas Liquids | 437,238 | 407,570 | 924,454 | ||||||||||||||||||||
| Natural Gas | 475,715 | 637,452 | 1,321,175 | ||||||||||||||||||||
| Gains (Losses) on Mark-to-Market Commodity Derivative Contracts | (99,608) | 61,924 | 834,273 | ||||||||||||||||||||
| Gathering, Processing and Marketing | 1,967,390 | 2,254,477 | 4,040,024 | ||||||||||||||||||||
| Gains (Losses) on Asset Dispositions, Net | 196,043 | (12,176) | 96,339 | ||||||||||||||||||||
| Other, Net | 81,386 | 47,464 | 49,950 | ||||||||||||||||||||
| Net Operating Revenues | 7,323,200 | [1] | 8,314,442 | [2] | 16,792,364 | [3] | |||||||||||||||||
| Depreciation, Depletion and Amortization | 3,365,390 | 3,139,863 | 3,684,943 | ||||||||||||||||||||
| Operating Income (Loss) | (1,192,338) | (6,566,282) | 5,074,911 | ||||||||||||||||||||
| Interest Income | 358 | 1,913 | 849 | ||||||||||||||||||||
| Other Income (Expense) | (15,703) | 6,461 | (14,953) | ||||||||||||||||||||
| Net Interest Expense | 298,125 | 274,606 | 269,166 | ||||||||||||||||||||
| Income (Loss) Before Income Taxes | (1,505,808) | (6,832,514) | 4,791,641 | ||||||||||||||||||||
| Income Tax Provision (Benefit) | (516,180) | (2,463,213) | 1,837,185 | ||||||||||||||||||||
| Additions to Oil and Gas Properties, Excluding Dry Hole Costs | 6,223,228 | 4,495,730 | 7,133,727 | ||||||||||||||||||||
| Total Property, Plant and Equipment, Net | 25,221,517 | 23,593,995 | 25,221,517 | 23,593,995 | 28,391,741 | ||||||||||||||||||
| Total Assets | 27,907,083 | 25,347,134 | 27,907,083 | 25,347,134 | 32,867,310 | ||||||||||||||||||
| Trinidad | |||||||||||||||||||||||
| Schedule of Segment Reporting Information By Segment [Abstract] | |||||||||||||||||||||||
| Crude Oil and Condensate | 9,600 | 13,122 | 29,604 | ||||||||||||||||||||
| Natural Gas Liquids | 0 | 0 | 0 | ||||||||||||||||||||
| Natural Gas | 234,108 | 368,639 | 483,071 | ||||||||||||||||||||
| Gains (Losses) on Mark-to-Market Commodity Derivative Contracts | 0 | 0 | 0 | ||||||||||||||||||||
| Gathering, Processing and Marketing | (1,131) | (1,342) | 6,064 | ||||||||||||||||||||
| Gains (Losses) on Asset Dispositions, Net | (145) | 393 | 0 | ||||||||||||||||||||
| Other, Net | (8) | (3) | 37 | ||||||||||||||||||||
| Net Operating Revenues | 242,424 | [1] | 380,809 | [2] | 518,776 | [3] | |||||||||||||||||
| Depreciation, Depletion and Amortization | 145,591 | 154,853 | 188,592 | ||||||||||||||||||||
| Operating Income (Loss) | 46,473 | 175,658 | 277,471 | ||||||||||||||||||||
| Interest Income | 932 | 389 | 253 | ||||||||||||||||||||
| Other Income (Expense) | 2,667 | 8,780 | 8,712 | ||||||||||||||||||||
| Net Interest Expense | 0 | 1,400 | 0 | ||||||||||||||||||||
| Income (Loss) Before Income Taxes | 50,072 | 183,427 | 286,436 | ||||||||||||||||||||
| Income Tax Provision (Benefit) | 64,281 | 63,502 | 98,559 | ||||||||||||||||||||
| Additions to Oil and Gas Properties, Excluding Dry Hole Costs | 75,407 | 102,358 | 76,138 | ||||||||||||||||||||
| Total Property, Plant and Equipment, Net | 274,850 | 350,766 | 274,850 | 350,766 | 382,719 | ||||||||||||||||||
| Total Assets | 889,253 | 886,826 | 889,253 | 886,826 | 865,674 | ||||||||||||||||||
| Other International | |||||||||||||||||||||||
| Schedule of Segment Reporting Information By Segment [Abstract] | |||||||||||||||||||||||
| Crude Oil and Condensate | [4] | 42,705 | 3,709 | 186,727 | |||||||||||||||||||
| Natural Gas Liquids | [4] | 12 | 88 | 9,597 | |||||||||||||||||||
| Natural Gas | [4] | 32,329 | 54,947 | 112,140 | |||||||||||||||||||
| Gains (Losses) on Mark-to-Market Commodity Derivative Contracts | [4] | 0 | 0 | 0 | |||||||||||||||||||
| Gathering, Processing and Marketing | [4] | 0 | 0 | 228 | |||||||||||||||||||
| Gains (Losses) on Asset Dispositions, Net | [4] | 9,937 | 2,985 | 411,251 | |||||||||||||||||||
| Other, Net | [4] | 25 | 448 | 4,257 | |||||||||||||||||||
| Net Operating Revenues | [4] | 85,008 | [1] | 62,177 | [2] | 724,200 | [3] | ||||||||||||||||
| Depreciation, Depletion and Amortization | [4] | 42,436 | 18,928 | 123,506 | |||||||||||||||||||
| Operating Income (Loss) | [4] | (79,416) | (295,455) | (110,559) | |||||||||||||||||||
| Interest Income | [4] | 1,329 | 1,167 | 1,137 | |||||||||||||||||||
| Other Income (Expense) | [4] | (40,126) | (16,794) | (41,048) | |||||||||||||||||||
| Net Interest Expense | [4] | (16,444) | (38,613) | (67,708) | |||||||||||||||||||
| Income (Loss) Before Income Taxes | [4] | (101,769) | (272,469) | (82,762) | |||||||||||||||||||
| Income Tax Provision (Benefit) | [4] | (8,920) | 2,670 | 144,084 | |||||||||||||||||||
| Additions to Oil and Gas Properties, Excluding Dry Hole Costs | [4] | 30,734 | 112,316 | 261,312 | |||||||||||||||||||
| Total Property, Plant and Equipment, Net | [4] | 210,711 | 265,960 | 210,711 | 265,960 | 398,184 | |||||||||||||||||
| Total Assets | [4] | $ 663,097 | $ 736,510 | $ 663,097 | $ 736,510 | $ 1,025,615 | |||||||||||||||||
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