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v3.21.2

Fair Value (Details) $ in Thousands | 3 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Jun. 23, 2021 USD ($) | Dec. 31, 2020 USD ($) | Jun. 17, 2020 USD ($)
Assets |  |  |  |  |  |  |
Derivative Assets, Fair Value, Gross Asset | $ 44,837 |  | $ 44,837 |  |  | $ 54,353 |
Liabilities |  |  |  |  |  |  |
Derivative Liability, Fair Value, Gross Liability | (661,335) |  | (661,335) |  |  | (222,520) |
Oil and Gas Property [Abstract] |  |  |  |  |  |  |
Property, Plant, and Equipment, Fair Value Disclosure | 0 |  | 0 |  |  | $ 0 |
Impairment of Proved Oil and Gas Properties | 0 | $ 0 | 0 | $ 956,700 |  |  |
Abandonment and impairment of unproved properties | 8,800 | 8,800 | 17,500 | 41,900 |  |  |
Impairment of Oil and Gas Properties | $ 8,750 | $ 8,750 | $ 17,500 | $ 998,513 |  |  |
1.50% Senior Secured Convertible Notes Due 2021 [Member] |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 1.50% |  | 1.50% |  |  | 1.50% |
Senior Notes, Principal amount | $ 65,485 |  | $ 65,485 |  |  | $ 65,485 |
Long-term Debt, Fair Value | $ 64,888 |  | $ 64,888 |  |  | $ 61,449 |
10.0% Senior Secured Notes due 2025 [Member] |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 10.00% |  | 10.00% |  |  | 10.00% |
Senior Notes, Principal amount | $ 446,675 |  | $ 446,675 |  |  | $ 446,675 | $ 446,700
Long-term Debt, Fair Value | $ 505,511 |  | $ 505,511 |  |  | $ 482,887 |
6.125% Senior Unsecured Notes due 2022 [Member] |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 6.125% |  | 6.125% |  |  | 6.125% |
Senior Notes, Principal amount | $ 0 |  | $ 0 |  |  | $ 212,403 |
Long-term Debt, Fair Value | $ 0 |  | $ 0 |  |  | $ 205,379 |
5.0% Senior Unsecured Notes due 2024 [Member] |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 5.00% |  | 5.00% |  |  | 5.00% |
Senior Notes, Principal amount | $ 104,769 |  | $ 104,769 |  |  | $ 277,034 |
Long-term Debt, Fair Value | $ 104,662 |  | $ 104,662 |  |  | $ 240,072 |
5.625% Senior Unsecured Notes due 2025 [Member] |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 5.625% |  | 5.625% |  |  | 5.625% |
Senior Notes, Principal amount | $ 349,118 |  | $ 349,118 |  |  | $ 349,118 |
Long-term Debt, Fair Value | $ 349,118 |  | $ 349,118 |  |  | $ 289,401 |
6.75% Senior Unsecured Notes due 2026 [Member] |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 6.75% |  | 6.75% |  |  | 6.75% |
Senior Notes, Principal amount | $ 419,235 |  | $ 419,235 |  |  | $ 419,235 |
Long-term Debt, Fair Value | $ 427,079 |  | $ 427,079 |  |  | $ 342,385 |
6.625% Senior Unsecured Notes due 2027 [Member] |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 6.625% |  | 6.625% |  |  | 6.625% |
Senior Notes, Principal amount | $ 416,791 |  | $ 416,791 |  |  | $ 416,791 |
Long-term Debt, Fair Value | $ 429,061 |  | $ 429,061 |  |  | 331,220 |
6.5% Senior Unsecured Notes Due 2028 [Member] |  |  |  |  |  |  |
Debt Instrument, Fair Value Disclosure [Abstract] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 6.50% |  | 6.50% |  | 6.50% |  |
Senior Notes, Principal amount | $ 400,000 |  | $ 400,000 |  | $ 400,000 | 0 |
Long-term Debt, Fair Value | 412,000 |  | 412,000 |  |  | 0 |
Fair Value, Nonrecurring [Member] | Measurement Input, Discount Rate [Member] | Oil and Gas Properties |  |  |  |  |  |  |
Oil and Gas Property [Abstract] |  |  |  |  |  |  |
Fair Value Assumptions, Measurement Input |  | 0.11 |  | 0.11 |  |  |
Not Designated as Hedging Instrument [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |
Derivative Assets, Fair Value, Gross Asset | 0 |  | 0 |  |  | 0 |
Liabilities |  |  |  |  |  |  |
Derivative Liability, Fair Value, Gross Liability | 0 |  | 0 |  |  | 0 |
Not Designated as Hedging Instrument [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |
Derivative Assets, Fair Value, Gross Asset | 44,837 |  | 44,837 |  |  | 54,353 |
Liabilities |  |  |  |  |  |  |
Derivative Liability, Fair Value, Gross Liability | 661,335 |  | 661,335 |  |  | 222,520 |
Not Designated as Hedging Instrument [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |
Assets |  |  |  |  |  |  |
Derivative Assets, Fair Value, Gross Asset | 0 |  | 0 |  |  | 0 |
Liabilities |  |  |  |  |  |  |
Derivative Liability, Fair Value, Gross Liability | $ 0 |  | $ 0 |  |  | $ 0 |

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