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Long-Term Debt (Details) - USD ($) |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jun. 17, 2020 | Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Long-Term Debt [Line Items] |  |  |  |  |  |
Long-term Line of Credit and Senior Notes, Noncurrent |  | $ 2,353,038,000 |  | $ 2,353,038,000 |  | $ 2,732,798,000
Gain on extinguishment of debt |  | $ 25,070,000 | $ 0 | $ 264,546,000 | $ 0 |
Senior Secured Notes, Senior Unsecured Notes, and 1.50% Senior Unsecured Convertible Notes due 2021 [Member] |  |  |  |  |  |
Long-Term Debt [Line Items] |  |  |  |  |  |
Gain on extinguishment of debt | $ 227,300,000 |  |  |  |  |

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