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Long-Term Debt Senior Notes (Details) - USD ($) $ in Thousands |  |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Aug. 20, 2018 | Jul. 16, 2018 | Jun. 15, 2018 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | $ 2,447,290 |  | $ 2,447,290 |  | $ 2,769,663
Loss on extinguishment of debt |  |  |  |  | (26,722) | $ 0 | (26,722) | $ (35) |
Cash paid for extinguishment of debt | [1] |  |  |  |  |  |  | 13 |
Non-cash loss on extinguishment of debt |  |  |  |  |  |  | 6,334 | $ 22 |
Senior Notes |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Principal Amount |  |  |  |  | 2,476,796 |  | 2,476,796 |  | 2,801,392
Unamortized Deferred Financing Costs |  |  |  |  | (29,506) |  | (29,506) |  | (31,729)
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | $ 2,447,290 |  | $ 2,447,290 |  | 2,769,663
6.50% Senior Notes due 2021 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.50% |  | 6.50% |  |
6.125% Senior Notes due 2022 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.125% |  | 6.125% |  |
6.50% Senior Notes due 2023 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.50% |  | 6.50% |  |
5.0% Senior Notes due 2024 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 5.00% |  | 5.00% |  |
5.625% Senior Notes due 2025 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 5.625% |  | 5.625% |  |
6.75% Senior Notes due 2026 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.75% |  | 6.75% |  |
Senior Notes | 6.50% Senior Notes due 2021 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.50% |  | 6.50% |  |
Principal Amount |  |  |  |  | $ 0 |  | $ 0 |  | 344,611
Unamortized Deferred Financing Costs |  |  |  |  | 0 |  | 0 |  | (2,656)
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | 0 |  | $ 0 |  | 341,955
Debt Instrument, Repurchased Face Amount |  |  |  | $ 344,611 |  |  |  |  |
Debt Instrument, Redemption Price, Percentage |  |  |  | 102.167% |  |  |  |  |
Debt Instrument, Repurchased Settlement Amount |  |  | $ 355,900 |  |  |  |  |  |
Loss on extinguishment of debt |  |  |  |  | 9,800 |  |  |  |
Cash paid for extinguishment of debt |  |  |  |  | 7,500 |  |  |  |
Non-cash loss on extinguishment of debt |  |  |  |  | $ 2,300 |  |  |  |
Senior Notes | 6.125% Senior Notes due 2022 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.125% |  | 6.125% |  |
Principal Amount |  |  |  |  | $ 476,796 |  | $ 476,796 |  | 561,796
Unamortized Deferred Financing Costs |  |  |  |  | (4,171) |  | (4,171) |  | (5,800)
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | 472,625 |  | 472,625 |  | 555,996
Debt Instrument, Repurchased Face Amount |  |  |  |  | $ 85,000 |  | $ 85,000 |  |
Senior Notes | 6.50% Senior Notes due 2023 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.50% |  | 6.50% |  |
Principal Amount |  |  |  |  | $ 0 |  | $ 0 |  | 394,985
Unamortized Deferred Financing Costs |  |  |  |  | 0 |  | 0 |  | (3,707)
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | 0 |  | 0 |  | 391,278
Debt Instrument, Repurchased Face Amount |  |  |  |  | $ 394,985 |  | $ 394,985 |  |
Senior Notes | 5.0% Senior Notes due 2024 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 5.00% |  | 5.00% |  |
Principal Amount |  |  |  |  | $ 500,000 |  | $ 500,000 |  | 500,000
Unamortized Deferred Financing Costs |  |  |  |  | (4,919) |  | (4,919) |  | (5,610)
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | $ 495,081 |  | $ 495,081 |  | 494,390
Senior Notes | 5.625% Senior Notes due 2025 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 5.625% |  | 5.625% |  |
Principal Amount |  |  |  |  | $ 500,000 |  | $ 500,000 |  | 500,000
Unamortized Deferred Financing Costs |  |  |  |  | (6,035) |  | (6,035) |  | (6,714)
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | $ 493,965 |  | $ 493,965 |  | 493,286
Senior Notes | 6.75% Senior Notes due 2026 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.75% |  | 6.75% |  |
Principal Amount |  |  |  |  | $ 500,000 |  | $ 500,000 |  | 500,000
Unamortized Deferred Financing Costs |  |  |  |  | (6,615) |  | (6,615) |  | (7,242)
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | $ 493,385 |  | $ 493,385 |  | 492,758
Senior Notes | 6.625% Senior Notes due 2027 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.625% |  | 6.625% |  |
Principal Amount |  | $ 500,000 |  |  | $ 500,000 |  | $ 500,000 |  | 0
Unamortized Deferred Financing Costs |  |  |  |  | (7,766) |  | (7,766) |  | 0
Principal Amount, Net of Unamortized Deferred Financing Costs |  |  |  |  | 492,234 |  | $ 492,234 |  | $ 0
Proceeds from Debt, Net of Issuance Costs |  | 492,100 |  |  |  |  |  |  |
Debt Issuance Costs, Gross |  | $ 7,900 |  |  |  |  |  |  |
Senior Notes | 6.125% Senior Notes Due 2022 and 6.50% Senior Notes Due 2023 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Repurchased Settlement Amount |  |  |  |  | 497,800 |  |  |  |
Loss on extinguishment of debt |  |  |  |  | 16,900 |  |  |  |
Cash paid for extinguishment of debt |  |  |  |  | 12,900 |  |  |  |
Non-cash loss on extinguishment of debt |  |  |  |  | $ 4,000 |  |  |  |
[1] | (1) Included as a component within the cash paid to repurchase Senior Notes, including premium line item on the accompanying statements of cash flows.

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