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v3.3.1.900

Fair Value Measurements (Details 2) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Period of New York Mercantile Exchange Strip Pricing Used for Price Forecast |  | 5 years |  |  |  |
Proved Oil and Gas Properties |  |  |  |  |  |
Period of New York Mercantile Exchange Strip Pricing Used for Price Forecast |  | 5 years |  |  |  |
Impairment of proved properties |  | $ 468,679 |  | $ 84,480 |  | $ 172,641
Proved Oil and Gas Property, Successful Effort Method |  | 7,606,405 |  | 7,348,436 |  |
Unproved Oil and Gas Property, Successful Effort Method |  | 284,538 |  | 532,498 |  |
Impairment of other property and equipment |  | 49,369 |  | 0 |  | 0
Property, Plant and Equipment, Other, Net |  | 153,100 |  | 334,356 |  |
Disposal Group, Not Discontinued Operation, Loss (Gain) on Write-down |  | 98,600 |  | 27,600 |  |
Oil and gas properties held for sale |  | $ 641 |  | $ 17,891 |  |
Net Profit Plan liability [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Fair Value Inputs, Discount Rate |  | 10.00% |  | 12.00% |  |
Period of New York Mercantile Exchange Strip Pricing Used for Price Forecast |  | 5 years |  |  |  |
Period Used for Price Assumptions of Strip Prices of Liabilities |  | 1 year |  |  |  |
Percentage change in commodity prices (as a percent) |  | 5.00% |  |  |  |
Change in liability due to change in commodity prices by 5 percent |  | $ 1,100 |  |  |  |
Percent Change in Discount Rate for Sensitivity Analysis |  | 1.00% |  |  |  |
Sensitivity Analysis Change in Liability Due to Change in Discount Rate |  | $ 300 |  |  |  |
Fair Value, NPP Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |
Net Profits Plan Liability: Beginning Balance |  | 27,136 |  | $ 56,985 |  | 78,827
Net increase (decrease) in liability | [1] | (12,238) |  | (12,492) |  | 3,527
Net settlements | [1],[2] | (7,287) |  | (17,357) |  | (25,369)
Transfers in (out) of Level 3 |  | 0 |  | 0 |  | 0
Net Profits Plan Liability: Ending balance |  | 7,611 |  | 27,136 |  | 56,985
Cash Payments Made or Accrued under Profit Sharing Plan Related to Divested Property |  | $ 3,800 |  | 8,300 |  | $ 10,300
Proved Oil and Gas Properties |  |  |  |  |  |
Period of New York Mercantile Exchange Strip Pricing Used for Price Forecast |  | 5 years |  |  |  |
6.625% Senior Notes Due 2019 [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Long-term Debt, Fair Value | [3] | $ 0 |  | 350,018 |  |
6.50% Senior Notes Due 2021 [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Long-term Debt, Fair Value |  | 262,938 |  | 343,000 |  |
6.125% Senior Notes Due 2022 [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Long-term Debt, Fair Value |  | 440,250 |  | 556,500 |  |
6.50% Senior Notes Due 2023 [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Long-term Debt, Fair Value |  | 296,000 |  | 379,000 |  |
5% Senior Notes Due 2024 [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Long-term Debt, Fair Value |  | 334,065 |  | 435,000 |  |
5.625% Senior Notes Due 2025 [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Long-term Debt, Fair Value | [3] | 326,875 |  | $ 0 |  |
Oil and Gas Properties [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Fair Value Inputs, Discount Rate |  |  |  | 12.00% |  |
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] |  |  |  |  |  |
Proved Oil and Gas Properties |  |  |  |  |  |
Proved Oil and Gas Property, Successful Effort Method |  | 124,184 | [4] | $ 33,423 | [5] |
Unproved Oil and Gas Property, Successful Effort Method | [4] | 0 |  | 0 |  |
Property, Plant and Equipment, Other, Net | [5] | $ 629 |  |  |  |
Oil and gas properties held for sale | [5] |  |  | $ 17,891 |  |
Minimum [Member] | Oil and Gas Properties [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Fair Value Inputs, Discount Rate |  | 10.00% |  |  |  |
Maximum [Member] | Oil and Gas Properties [Member] |  |  |  |  |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |  |
Fair Value Inputs, Discount Rate |  | 15.00% |  |  |  |
[1] | Net changes in the Company’s Net Profits Plan liability are shown in the Change in Net Profits Plan liability line item of the accompanying statements of operations.
[2] | Settlements represent cash payments made or accrued under the Net Profits Plan. The amounts in the table include cash payments made or accrued under the Net Profits Plan of $3.8 million, $8.3 million, and $10.3 million for the years ended December 31, 2015, 2014, and 2013, respectively, as a result of the divestitures of properties subject to the Net Profits Plan.
[3] | The 2019 Notes were fully redeemed on June 22, 2015 and the 2025 Notes were issued on May 21, 2015.
[4] | This represents a non-financial asset that is measured at fair value on a nonrecurring basis.
[5] | This represents a non-financial asset that is measured at fair value on a nonrecurring basis.

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