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Senior Unsecured Notes (Details) - USD ($) $ in Thousands |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 17, 2020 | May 05, 2020 | Sep. 30, 2020 | Mar. 31, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Repayment of 1.50% Senior Convertible Notes due 2021 |  |  |  |  |  | $ 53,508 | $ 0 |
Gain on extinguishment of debt |  |  | $ 25,070 |  | $ 0 | 264,546 | 0 |
Senior Notes, net |  |  | 2,175,038 |  |  | 2,175,038 |  | $ 2,610,298
Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Unsecured Notes, exchanged or repurchased face amount | $ 611,900 |  |  |  |  |  |  |
Senior Unsecured Notes, Redemption Price, Percentage |  | 80.00% |  |  |  |  |  |
Senior Notes, Principal amount |  |  | 1,732,658 |  |  | 1,732,658 |  | 2,649,296
Senior Unsecured Notes, unamortized deferred financing costs |  |  | 15,011 |  |  | 15,011 |  | 38,998
Senior Notes, net |  |  | 1,717,647 |  |  | 1,717,647 |  | 2,610,298
Senior Unsecured Notes and 1.50% Senior Unsecured Convertible Notes due 2021 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Unsecured Notes, exchanged or repurchased face amount | 718,911 |  |  |  |  |  |  |
Interest Paid, Senior Unsecured Notes, Accrued and Unpaid | 8,900 |  |  |  |  |  |  |
Senior Unsecured Notes and 1.50% Senior Unsecured Convertible Notes due 2021 [Member] | Accelerated unamortized deferred financing costs [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Gain on Extinguishment of Debt, Non Cash Portion | 5,600 |  |  |  |  |  |  |
6.125% Senior Unsecured Notes Due 2022 and 5.0% Senior Unsecured Notes Due 2024 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Unsecured Notes, repurchased settlement amount |  |  | 65,900 |  |  | $ 65,900 |  |
Gain on extinguishment of debt |  |  | 25,100 |  |  |  |  |
Discount realized on extinguishment of debt |  |  | 25,500 |  |  |  |  |
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] |  |  |  |  |  |  |  |
Gain on Extinguishment of Debt, Non Cash Portion |  |  | $ 480 |  |  |  |  |
6.125% Senior Unsecured Notes due 2022 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  | 6.125% |  |  | 6.125% |  |
Senior Unsecured Notes, exchanged or repurchased face amount | 141,701 |  | $ 62,500 | $ 40,700 |  | $ 62,500 |  |
Senior Unsecured Notes, repurchased settlement amount |  |  |  | 28,300 |  |  |  |
Gain on extinguishment of debt |  |  |  | 12,200 |  |  |  |
Discount realized on extinguishment of debt |  |  |  | 12,400 |  |  |  |
Senior Notes, Principal amount |  |  | 231,881 |  |  | 231,881 |  | 476,796
Senior Unsecured Notes, unamortized deferred financing costs |  |  | 1,055 |  |  | 1,055 |  | 2,920
Senior Notes, net |  |  | $ 230,826 |  |  | $ 230,826 |  | 473,876
6.125% Senior Unsecured Notes due 2022 [Member] | Accelerated unamortized deferred financing costs [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Gain on Extinguishment of Debt, Non Cash Portion |  |  |  | $ 235 |  |  |  |
5.0% Senior Unsecured Notes due 2024 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  | 5.00% |  |  | 5.00% |  |
Senior Unsecured Notes, exchanged or repurchased face amount | 155,339 |  | $ 29,000 |  |  | $ 29,000 |  |
Senior Notes, Principal amount |  |  | 315,633 |  |  | 315,633 |  | 500,000
Senior Unsecured Notes, unamortized deferred financing costs |  |  | 1,941 |  |  | 1,941 |  | 3,766
Senior Notes, net |  |  | $ 313,692 |  |  | $ 313,692 |  | 496,234
5.625% Senior Unsecured Notes due 2025 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  | 5.625% |  |  | 5.625% |  |
Senior Unsecured Notes, exchanged or repurchased face amount | 150,882 |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  | $ 349,118 |  |  | $ 349,118 |  | 500,000
Senior Unsecured Notes, unamortized deferred financing costs |  |  | 2,950 |  |  | 2,950 |  | 4,903
Senior Notes, net |  |  | $ 346,168 |  |  | $ 346,168 |  | 495,097
6.75% Senior Unsecured Notes due 2026 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  | 6.75% |  |  | 6.75% |  |
Senior Unsecured Notes, exchanged or repurchased face amount | 80,765 |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  | $ 419,235 |  |  | $ 419,235 |  | 500,000
Senior Unsecured Notes, unamortized deferred financing costs |  |  | 4,145 |  |  | 4,145 |  | 5,571
Senior Notes, net |  |  | $ 415,090 |  |  | $ 415,090 |  | 494,429
6.625% Senior Unsecured Notes due 2027 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  | 6.625% |  |  | 6.625% |  |
Senior Unsecured Notes, exchanged or repurchased face amount | $ 83,209 |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  | $ 416,791 |  |  | $ 416,791 |  | 500,000
Senior Unsecured Notes, unamortized deferred financing costs |  |  | 4,920 |  |  | 4,920 |  | 6,601
Senior Notes, net |  |  | $ 411,871 |  |  | $ 411,871 |  | 493,399
1.50% Senior Unsecured Convertible Notes Due 2021 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 1.50% |  | 1.50% |  |  | 1.50% |  |
Senior Unsecured Notes, exchanged or repurchased face amount | $ 107,015 |  |  |  |  |  |  |
Repayment of 1.50% Senior Convertible Notes due 2021 | 53,500 |  |  |  |  |  |  |
Interest Expense, Debt |  |  |  |  | $ 2,800 |  | $ 8,200 |
Senior Notes, Principal amount |  |  | $ 0 |  |  | $ 0 |  | 172,500
Senior Unsecured Notes, unamortized deferred financing costs |  |  | 0 |  |  | 0 |  | 15,237
Senior Notes, net |  |  | $ 0 |  |  | $ 0 |  | 157,263
1.50% Senior Unsecured Convertible Notes due 2021, Unamortized Debt Discount |  |  |  |  |  |  |  | $ (13,900)
1.50% Senior Unsecured Convertible Notes Due 2021 [Member] | Accelerated unamortized debt discount [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Gain on Extinguishment of Debt, Non Cash Portion | $ 6,100 |  |  |  |  |  |  |

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