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Long-term Debt (Details) - USD ($) $ in Thousands |  |  |  |  |  |  |  |  | 2 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 23, 2021 | Jun. 17, 2020 | Aug. 20, 2018 | Sep. 12, 2016 | Aug. 12, 2016 | May 21, 2015 | Nov. 17, 2014 | May 20, 2013 | Feb. 24, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Feb. 14, 2022 | Feb. 10, 2022
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility |  |  |  |  |  |  |  |  |  | $ 0 | $ 93,000 |  |  |
Secured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  |  | 460,656 |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  | 1,673,452 | 1,660,663 |  |  |
Total long-term debt, net |  |  |  |  |  |  |  |  |  | 2,081,164 | 2,214,319 |  |  |
Net gain (loss) on extinguishment of debt |  |  |  |  |  |  |  |  |  | $ (2,139) | 280,081 | $ 0 |  |
Debt Instrument, Covenant Description |  |  |  |  |  |  |  |  |  | (a) total funded debt, as defined in the Credit Agreement, to 12-month trailing adjusted EBITDAX ratio cannot be greater than 4.00 to 1.00 on the last day of each fiscal quarter; and (b) adjusted current ratio, as defined in the Credit Agreement, cannot be less than 1.00 to 1.00 as of the last day of any fiscal quarter. |  |  |  |
Debt Instrument, Covenant Compliance |  |  |  |  |  |  |  |  |  | The Company was in compliance with all covenants under the Credit Agreement and the indentures governing the Senior Notes as of December 31, 2021, and through the filing of this report. |  |  |  |
Capitalized interest costs |  |  |  |  |  |  |  |  |  | $ 15,000 | 15,800 | $ 18,500 |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility |  |  |  |  |  |  |  |  |  | 0 | 93,000 |  |  |
Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Covenant Compliance |  |  |  |  |  |  |  |  | The Company was in compliance with all covenants under the Credit Agreement and the indentures governing the Senior Notes as of December 31, 2021, and through the filing of this report. |  |  |  |  |
Subsequent Event | Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0
5.0% Senior Unsecured Notes Due 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  | 104,366 | 275,458 |  |  |
Senior Notes, Principal amount |  |  |  |  |  |  |  | $ 500,000 |  | $ 104,769 | 277,034 |  |  |
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  |  |  |  |  |  | $ 490,200 |  |  |  |  |  |
Senior Unsecured Notes, repurchased, retired or redeemed face amount | $ 172,300 | $ 155,339 |  |  |  |  |  |  |  |  | $ 67,600 |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  |  |  |  | 5.00% |  | 5.00% | 5.00% |  |  |
Convertible Notes Debt Issuance Costs |  |  |  |  |  |  |  | $ 9,800 |  |  |  |  |  |
5.0% Senior Unsecured Notes Due 2024 [Member] | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 104,800 |
6.5% Senior Unsecured Notes Due 2028 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  | $ 393,321 | $ 0 |  |  |
Senior Notes, Principal amount | 400,000 |  |  |  |  |  |  |  |  | $ 400,000 | $ 0 |  |  |
Proceeds from Senior Unsecured Notes, Net of debt issuance costs | $ 392,800 |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 6.50% |  |  |  |  |  |  |  |  | 6.50% | 6.50% |  |  |
Convertible Notes Debt Issuance Costs | $ 7,200 |  |  |  |  |  |  |  |  |  |  |  |  |
6.125% Senior Unsecured Notes Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  | $ 0 | $ 211,548 |  |  |
Senior Notes, Principal amount |  |  |  |  |  |  | $ 600,000 |  |  | 0 | 212,403 |  |  |
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  |  |  |  |  | $ 590,000 |  |  |  |  |  |  |
Senior Unsecured Notes, repurchased, retired or redeemed face amount | $ 193,100 | 141,701 |  |  |  |  |  |  |  | $ 19,300 | $ 122,700 |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  |  |  | 6.125% |  |  | 6.125% | 6.125% |  |  |
Convertible Notes Debt Issuance Costs |  |  |  |  |  |  | $ 10,000 |  |  |  |  |  |  |
6.125% Senior Unsecured Notes Due 2022 and 5.0% Senior Unsecured Notes Due 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes, Settlement Amount |  |  |  |  |  |  |  |  |  | $ 385,300 | $ 136,500 |  |  |
Net gain (loss) on extinguishment of debt |  |  |  |  |  |  |  |  |  | (2,100) | 52,800 |  |  |
Debt Instrument, Repurchase Premium |  |  |  |  |  |  |  |  |  | 600 |  |  |  |
Senior Unsecured Notes, Repurchase Discount |  |  |  |  |  |  |  |  |  |  | (53,800) |  |  |
6.125% Senior Unsecured Notes Due 2022 and 5.0% Senior Unsecured Notes Due 2024 [Member] | Accelerated Unamortized Deferred Financing Costs [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Write off of Deferred Debt Issuance Cost |  |  |  |  |  |  |  |  |  | 1,500 | 1,000 |  |  |
1.50% Senior Unsecured Convertible Notes Due 2021 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  |  |  | $ 172,500 |  |  |  |  |  |  |  |  |
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  |  |  | $ 166,600 |  |  |  |  |  |  |  |  |
Senior Unsecured Notes, repurchased, retired or redeemed face amount |  | 107,000 |  |  |  |  |  |  |  |  |  |  |  |
Repayments of Convertible Debt |  | 53,500 |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 1.50% |  |  |  |  |  |  |  |  |
Convertible Notes Debt Issuance Costs |  |  |  |  | $ 5,900 |  |  |  |  |  |  |  |  |
10.0% Senior Secured Notes due 2025 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  | 407,712 | 397,174 |  |  |
Senior Notes, Principal amount |  | $ 446,700 |  |  |  |  |  |  |  | $ 446,675 | $ 446,675 |  |  |
Senior Notes, interest rate, stated percentage |  | 10.00% |  |  |  |  |  |  |  | 10.00% | 10.00% |  |  |
Convertible Notes Debt Issuance Costs |  | $ 13,100 |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes, Senior Unsecured Notes, and 1.50% Senior Unsecured Convertible Notes Due 2021 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on extinguishment of debt |  | 227,300 |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes, Senior Unsecured Notes, and 1.50% Senior Unsecured Convertible Notes Due 2021 [Member] | Accelerated Unamortized Debt Discount [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Write off of Deferred Debt Issuance Cost |  | 6,100 |  |  |  |  |  |  |  |  |  |  |  |
Senior Secured Notes, Senior Unsecured Notes, and 1.50% Senior Unsecured Convertible Notes Due 2021 [Member] | Accelerated Unamortized Deferred Financing Costs [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Write off of Deferred Debt Issuance Cost |  | 5,600 |  |  |  |  |  |  |  |  |  |  |  |
5.625% Senior Unsecured Notes Due 2025 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  | $ 346,958 | $ 346,326 |  |  |
Senior Notes, Principal amount |  |  |  |  |  | $ 500,000 |  |  |  | $ 349,118 | $ 349,118 |  |  |
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  |  |  |  | $ 491,000 |  |  |  |  |  |  |  |
Senior Unsecured Notes, repurchased, retired or redeemed face amount |  | 150,882 |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  |  | 5.625% |  |  |  | 5.625% | 5.625% |  |  |
Convertible Notes Debt Issuance Costs |  |  |  |  |  | $ 9,000 |  |  |  |  |  |  |  |
6.75% Senior Unsecured Notes Due 2026 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  | $ 415,965 | $ 415,265 |  |  |
Senior Notes, Principal amount |  |  |  | $ 500,000 |  |  |  |  |  | $ 419,235 | $ 419,235 |  |  |
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  |  | $ 491,600 |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes, repurchased, retired or redeemed face amount |  | 80,765 |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  | 6.75% |  |  |  |  |  | 6.75% | 6.75% |  |  |
Convertible Notes Debt Issuance Costs |  |  |  | $ 8,400 |  |  |  |  |  |  |  |  |  |
6.625% Senior Unsecured Notes Due 2027 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  |  |  |  | $ 412,842 | $ 412,066 |  |  |
Senior Notes, Principal amount |  |  | $ 500,000 |  |  |  |  |  |  | $ 416,791 | $ 416,791 |  |  |
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  | $ 492,100 |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes, repurchased, retired or redeemed face amount |  | 83,209 |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  | 6.625% |  |  |  |  |  |  | 6.625% | 6.625% |  |  |
Convertible Notes Debt Issuance Costs |  |  | $ 7,900 |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  |  |  |  |  |  |  |  | $ 1,689,913 | $ 1,674,581 |  |  |
Senior Unsecured Notes, repurchased, retired or redeemed face amount |  | $ 611,896 |  |  |  |  |  |  |  |  |  |  |  |

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- Definition The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=99376301&loc=d3e1336-112600 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=99376301&loc=d3e1314-112600 + Details
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- Definition The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585 + Details
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- Definition The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585 + Details
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- Definition Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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