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v3.21.1

Fair Value (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($)
Assets |  |  |
Derivative Assets, Fair Value, Gross Asset | $ 34,426 |  | $ 54,353
Liabilities |  |  |
Derivative Liability, Fair Value, Gross Liability | (439,397) |  | $ (222,520)
Oil and Gas Property [Abstract] |  |  |
Property, Plant, and Equipment, Fair Value Disclosure | 0 |  |
Impairment of proved oil and gas properties and related support equipment | 0 | $ 956,700 |
Abandonment and impairment of unproved properties | $ 8,800 | $ 33,100 |
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%
Senior Notes, Principal amount | $ 65,485 |  | $ 65,485
Long-term Debt, Fair Value | $ 63,864 |  | $ 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%
Senior Notes, Principal amount | $ 446,675 |  | $ 446,675
Long-term Debt, Fair Value | $ 502,858 |  | $ 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%
Senior Notes, Principal amount | $ 212,403 |  | $ 212,403
Long-term Debt, Fair Value | $ 209,633 |  | $ 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%
Senior Notes, Principal amount | $ 277,034 |  | $ 277,034
Long-term Debt, Fair Value | $ 261,936 |  | $ 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%
Senior Notes, Principal amount | $ 349,118 |  | $ 349,118
Long-term Debt, Fair Value | $ 323,007 |  | $ 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%
Senior Notes, Principal amount | $ 419,235 |  | $ 419,235
Long-term Debt, Fair Value | $ 387,373 |  | $ 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%
Senior Notes, Principal amount | $ 416,791 |  | $ 416,791
Long-term Debt, Fair Value | 384,323 |  | 331,220
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 |
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
Liabilities |  |  |
Derivative Liability, Fair Value, Gross Liability | 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 | 34,426 |  | 54,353
Liabilities |  |  |
Derivative Liability, Fair Value, Gross Liability | 439,397 |  | 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
Liabilities |  |  |
Derivative Liability, Fair Value, Gross Liability | $ 0 |  | $ 0

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