XML 79 R58.htm IDEA: XBRL DOCUMENT
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Fair Value Measurements (Details 2) - USD ($) $ in Thousands, shares in Millions |  | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 21, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Sep. 12, 2016 | May 21, 2015 | Nov. 17, 2014 | May 20, 2013 | Jun. 29, 2012 | Nov. 08, 2011
Proved Oil and Gas Properties |  |  |  |  |  |  |  |  |  |
Impairment of proved properties |  | $ 3,806 | $ 354,614 | $ 468,679 |  |  |  |  |  |
Abandonment and impairment of unproved properties |  | 12,272 | 80,367 | 78,643 |  |  |  |  |  |
Impairment of other property and equipment |  | $ 0 | 0 | $ 49,369 |  |  |  |  |  |
6.50% Senior Notes Due 2021 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.50% |  |  |  |  |  |  |  |
Senior Notes, face amount |  |  | 346,955 |  |  |  |  |  |  | $ 350,000
6.125% Senior Notes Due 2022 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.125% |  |  |  |  |  |  |  |
Senior Notes, face amount |  |  | 561,796 |  |  |  | $ 600,000 |  |  |
6.50% Senior Notes Due 2023 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.50% |  |  |  |  |  |  |  |
Senior Notes, face amount |  |  | 394,985 |  |  |  |  |  | $ 400,000 |
5% Senior Notes Due 2024 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 5.00% |  |  |  |  |  |  |  |
Senior Notes, face amount |  |  | 500,000 |  |  |  |  | $ 500,000 |  |
5.625% Senior Notes Due 2025 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 5.625% |  |  |  |  |  |  |  |
Senior Notes, face amount |  |  | 500,000 |  |  | $ 500,000 |  |  |  |
6.75% Senior Notes Due 2026 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.75% |  |  |  |  |  |  |  |
Senior Notes, face amount |  |  | 500,000 |  | $ 500,000 |  |  |  |  |
Oil and Gas Properties [Member] |  |  |  |  |  |  |  |  |  |
Proved Oil and Gas Properties |  |  |  |  |  |  |  |  |  |
Period of New York Mercantile Exchange Strip Pricing Used for Price Forecast |  | 5 years |  |  |  |  |  |  |  |
Minimum [Member] | Oil and Gas Properties [Member] |  |  |  |  |  |  |  |  |  |
Proved Oil and Gas Properties |  |  |  |  |  |  |  |  |  |
Fair Value Inputs, Discount Rate |  | 10.00% |  |  |  |  |  |  |  |
Maximum [Member] | Oil and Gas Properties [Member] |  |  |  |  |  |  |  |  |  |
Proved Oil and Gas Properties |  |  |  |  |  |  |  |  |  |
Fair Value Inputs, Discount Rate |  | 15.00% |  |  |  |  |  |  |  |
Senior Notes [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, face amount |  | $ 2,801,392 | 2,803,736 |  |  |  |  |  |  |
Senior Notes [Member] | 6.50% Senior Notes Due 2021 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.50% |  |  |  |  |  |  |  |
Senior Notes, face amount |  | $ 344,611 | 346,955 |  |  |  |  |  |  |
Long-term Debt, Fair Value |  | $ 351,682 | 354,546 |  |  |  |  |  |  |
Senior Notes [Member] | 6.125% Senior Notes Due 2022 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.125% |  |  |  |  |  |  |  |
Senior Notes, face amount |  | $ 561,796 | 561,796 |  |  |  |  |  |  |
Long-term Debt, Fair Value |  | $ 571,627 | 570,925 |  |  |  |  |  |  |
Senior Notes [Member] | 6.50% Senior Notes Due 2023 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.50% |  |  |  |  |  |  |  |
Senior Notes, face amount |  | $ 394,985 | 394,985 |  |  |  |  |  |  |
Long-term Debt, Fair Value |  | $ 403,434 | 403,134 |  |  |  |  |  |  |
Senior Notes [Member] | 5% Senior Notes Due 2024 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 5.00% |  |  |  |  |  |  |  |
Senior Notes, face amount |  | $ 500,000 | 500,000 |  |  |  |  |  |  |
Long-term Debt, Fair Value |  | $ 483,440 | 475,975 |  |  |  |  |  |  |
Senior Notes [Member] | 5.625% Senior Notes Due 2025 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 5.625% |  |  |  |  |  |  |  |
Senior Notes, face amount |  | $ 500,000 | 500,000 |  |  |  |  |  |  |
Long-term Debt, Fair Value |  | $ 494,355 | 485,000 |  |  |  |  |  |  |
Senior Notes [Member] | 6.75% Senior Notes Due 2026 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.75% |  |  |  |  |  |  |  |
Senior Notes, face amount |  | $ 500,000 | 500,000 |  |  |  |  |  |  |
Long-term Debt, Fair Value |  | $ 516,350 | 516,565 |  |  |  |  |  |  |
Convertible Debt [Member] | 1.50% Senior Convertible Notes Due 2021 [Domain] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 1.50% |  |  |  |  |  |  |  |
Senior Notes, face amount |  | $ 172,500 | 172,500 |  |  |  |  |  |  |
Long-term Debt, Fair Value |  | $ 168,291 | $ 202,189 |  |  |  |  |  |  |
QStar Acquisition 2016 [Member] |  |  |  |  |  |  |  |  |  |
Proved Oil and Gas Properties |  |  |  |  |  |  |  |  |  |
Private issuance of Common Stock for an acquisition | 13.4 |  |  |  |  |  |  |  |  |

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