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Senior Secured Notes (Details) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2020 USD ($) $ / shares | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Jun. 17, 2020 USD ($) | May 05, 2020 USD ($) | Aug. 12, 2016 USD ($)
Senior Notes [Line Items] |  |  |  |  |  |
Senior Notes, net | $ 2,121,319,000 | $ 2,610,298,000 |  |  |  |
Permitted Second Lien Debt | 1,000,000,000.0 |  |  |  |  |
Increase to Permitted Second Lien Debt |  |  |  |  | $ 827,500,000 |
Permitted Second Lien Debt, Remaining Borrowing Capacity | 380,800,000 |  |  |  |  |
Senior Secured Notes |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |
Principal amount | 512,160,000 |  |  |  |  |
Senior Notes, unamortized debt discount | 39,771,000 |  |  |  |  |
Unamortized deferred financing costs | (11,733,000) |  |  |  |  |
Senior Notes, net | $ 460,656,000 | 0 |  |  |  |
10.0% Senior Secured Notes due 2025 [Member] |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 10.00% |  |  |  |  |
Principal amount | $ 446,675,000 | 0 |  | $ 446,700,000 |  |
Senior Notes, unamortized debt discount | 37,943,000 |  |  |  |  |
Unamortized deferred financing costs | (11,558,000) |  |  |  |  |
Senior Notes, net | 397,174,000 |  |  |  |  |
Senior Notes debt issuance costs | $ 13,100,000 |  |  |  |  |
Debt Instrument, Senior Notes, Initial Fair Value |  |  |  | $ 405,000,000.0 |  |
1.50% Senior Secured Convertible Notes Due 2021 [Member] |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 1.50% |  |  |  |  |
Principal amount | $ 65,485,000 | $ 0 |  |  |  |
Senior Notes, unamortized debt discount | 1,828,000 |  |  |  |  |
Unamortized deferred financing costs | (175,000) |  |  |  |  |
Senior Notes, net | 63,482,000 |  |  |  |  |
Senior Convertible Notes, interest expense | $ 7,700,000 |  |  |  |  |
Senior Convertible Notes, conversion rate | 24.6914 |  |  |  |  |
Senior Convertible Notes, principal amount of note | $ 1,000 |  |  |  |  |
Senior Convertible Notes, conversion price | $ / shares | $ 40.50 |  |  |  |  |
1.50% Senior Unsecured Convertible Notes Due 2021 [Member] |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 1.50% | 1.50% |  |  |  |
Principal amount | $ 0 | $ 172,500,000 |  |  |  | $ 172,500,000
Senior Notes, unamortized debt discount |  | 13,900,000 |  |  |  |
Unamortized deferred financing costs | 0 | (15,237,000) |  |  |  |
Senior Notes, net | $ 0 | 157,263,000 |  |  |  |
Senior Notes debt issuance costs |  |  |  |  |  | $ 5,900,000
Senior Convertible Notes, interest expense |  | $ 11,000,000.0 | $ 10,500,000 |  |  |

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