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Long-Term Debt (Details) - USD ($) $ in Thousands |  |  |  | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Oct. 28, 2021 | Jun. 23, 2021 | Jun. 17, 2020 | Sep. 30, 2021 | Jun. 30, 2021 | Sep. 30, 2020 | Jun. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Oct. 21, 2021 | Dec. 31, 2020
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility |  |  |  | $ 0 |  |  |  | $ 0 |  |  | $ 93,000
Secured Long-term Debt, Noncurrent |  |  |  | 405,007 |  |  |  | 405,007 |  |  | 460,656
Unsecured Long-term Debt, Noncurrent |  |  |  | 1,672,623 |  |  |  | 1,672,623 |  |  | 1,660,663
Total long-term debt, net |  |  |  | 2,077,630 |  |  |  | 2,077,630 |  |  | 2,214,319
Gain (loss) on extinguishment of debt |  |  |  | 5 |  | $ 25,070 |  | $ (2,139) | $ 264,546 |  |
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 September 30, 2021, and through the filing of this report. |  |  |
Capitalized interest costs |  |  |  | 3,500 |  | 4,800 |  | $ 12,500 | 11,600 |  |
6.5% Senior Unsecured Notes Due 2028 |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  | 393,067 |  |  |  | 393,067 |  |  | 0
Senior Notes, Principal amount |  | $ 400,000 |  | $ 400,000 |  |  |  | $ 400,000 |  |  | $ 0
Senior Notes, interest rate, stated percentage |  | 6.50% |  | 6.50% |  |  |  | 6.50% |  |  | 6.50%
Debt Instrument, Maturity Date |  | Jul. 15, 2028 |  |  |  |  |  |  |  |  |
Proceeds from Debt, Net of Issuance Costs |  | $ 392,800 |  |  |  |  |  |  |  |  |
Senior Secured Notes, Debt Issuance Costs, Gross |  | 7,200 |  |  |  |  |  |  |  |  |
6.125% Senior Unsecured Notes due 2022 |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  | $ 0 |  |  |  | $ 0 |  |  | $ 211,548
Senior Notes, Principal amount |  |  |  | $ 0 |  |  |  | $ 0 |  |  | $ 212,403
Senior Notes, interest rate, stated percentage |  |  |  | 6.125% |  |  |  | 6.125% |  |  | 6.125%
Senior Unsecured Notes, exchanged or repurchased face amount |  | 193,100 |  |  | $ 19,300 | 103,200 |  |  | 103,200 |  |
5.0% Senior Unsecured Notes due 2024 |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  | $ 104,318 |  |  |  | $ 104,318 |  |  | $ 275,458
Senior Notes, Principal amount |  |  |  | $ 104,769 |  |  |  | $ 104,769 |  |  | $ 277,034
Senior Notes, interest rate, stated percentage |  |  |  | 5.00% |  |  |  | 5.00% |  |  | 5.00%
Senior Unsecured Notes, exchanged or repurchased face amount |  | $ 172,300 |  |  |  | 29,000 |  |  | 29,000 |  |
6.125% Senior Unsecured Notes Due 2022 and 5.0% Senior Unsecured Notes Due 2024 [Member] |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Notes, repurchased settlement amount |  |  |  |  | 385,300 | 94,200 |  |  | 94,200 |  |
Gain (loss) on extinguishment of debt |  |  |  |  | (2,100) | 25,100 |  |  | 37,300 |  |
Debt Instrument, Repurchase Premium |  |  |  |  | 600 |  |  |  |  |  |
Discount realized on extinguishment of debt |  |  |  |  |  | (25,500) |  |  | (37,900) |  |
6.125% Senior Unsecured Notes Due 2022 and 5.0% Senior Unsecured Notes Due 2024 [Member] | Accelerated unamortized deferred financing costs [Member] |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Write off of Deferred Debt Issuance Cost |  |  |  |  | $ 1,500 | $ 500 |  |  | $ 700 |  |
1.50% Senior Unsecured Convertible Notes Due 2021 [Member] |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  |  | 1.50% |  |  | 1.50% |  |
Senior Unsecured Notes, exchanged or repurchased face amount |  |  | $ 107,000 |  |  |  |  |  |  |  |
Repayment of 1.50% Senior Convertible Notes due 2021 |  |  | 53,500 |  |  |  |  |  |  |  |
10.0% Senior Secured Notes due 2025 |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Secured Long-term Debt, Noncurrent |  |  |  | $ 405,007 |  |  |  | $ 405,007 |  |  | $ 397,174
Senior Notes, Principal amount |  |  | 446,700 | $ 446,675 |  |  |  | $ 446,675 |  |  | $ 446,675
Senior Notes, interest rate, stated percentage |  |  |  | 10.00% |  |  |  | 10.00% |  |  | 10.00%
Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  |  | $ 1,689,913 |  |  |  | $ 1,689,913 |  |  | $ 1,674,581
Senior Unsecured Notes, exchanged or repurchased face amount |  |  | $ 611,900 |  |  |  |  |  |  |  |
Senior Secured Notes, Senior Unsecured Notes, and 1.50% Senior Unsecured Convertible Notes Due 2021 |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Gain (loss) on extinguishment of debt |  |  |  |  |  |  | $ 227,300 |  |  |  |
Senior Secured Notes, Senior Unsecured Notes, and 1.50% Senior Unsecured Convertible Notes Due 2021 | Accelerated unamortized deferred financing costs [Member] |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Write off of Deferred Debt Issuance Cost |  |  |  |  |  |  | 5,600 |  |  |  |
Senior Secured Notes, Senior Unsecured Notes, and 1.50% Senior Unsecured Convertible Notes Due 2021 | Accelerated Unamortized Debt Discount |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Write off of Deferred Debt Issuance Cost |  |  |  |  |  |  | $ 6,100 |  |  |  |
Subsequent Event |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [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 September 30, 2021, and through the filing of this report. |  |  |  |  |  |  |  |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility |  |  |  | $ 0 |  |  |  | $ 0 |  |  | $ 93,000
Revolving Credit Facility [Member] | Subsequent Event |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility |  |  |  |  |  |  |  |  |  | $ 0 |

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