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Senior Unsecured Notes (Details) - USD ($) $ in Thousands | Jun. 23, 2021 | Aug. 20, 2018 | Sep. 12, 2016 | May 21, 2015 | Nov. 17, 2014 | May 20, 2013 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | --- | --- | --- | --- | --- | ---
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  | $ 1,673,452 | $ 1,660,663
6.125% Senior Unsecured Notes Due 2022 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  | 6.125% |  | 6.125% | 6.125%
Senior Notes, Principal amount |  |  |  |  | $ 600,000 |  | $ 0 | $ 212,403
Unamortized Debt Issuance Expense |  |  |  |  |  |  | 0 | 855
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  | $ 0 | $ 211,548
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  |  |  | 590,000 |  |  |
Senior Notes Debt Issuance Costs |  |  |  |  | $ 10,000 |  |  |
5.0% Senior Unsecured Notes Due 2024 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  |  |  | 5.00% | 5.00% | 5.00%
Senior Notes, Principal amount |  |  |  |  |  | $ 500,000 | $ 104,769 | $ 277,034
Unamortized Debt Issuance Expense |  |  |  |  |  |  | 403 | 1,576
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  | $ 104,366 | $ 275,458
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  |  |  |  | 490,200 |  |
Senior Notes Debt Issuance Costs |  |  |  |  |  | $ 9,800 |  |
5.625% Senior Unsecured Notes Due 2025 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  |  | 5.625% |  |  | 5.625% | 5.625%
Senior Notes, Principal amount |  |  |  | $ 500,000 |  |  | $ 349,118 | $ 349,118
Unamortized Debt Issuance Expense |  |  |  |  |  |  | 2,160 | 2,792
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  | $ 346,958 | $ 346,326
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  |  | 491,000 |  |  |  |
Senior Notes Debt Issuance Costs |  |  |  | $ 9,000 |  |  |  |
6.75% Senior Unsecured Notes Due 2026 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  |  | 6.75% |  |  |  | 6.75% | 6.75%
Senior Notes, Principal amount |  |  | $ 500,000 |  |  |  | $ 419,235 | $ 419,235
Unamortized Debt Issuance Expense |  |  |  |  |  |  | 3,270 | 3,970
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  | $ 415,965 | $ 415,265
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  |  | 491,600 |  |  |  |  |
Senior Notes Debt Issuance Costs |  |  | $ 8,400 |  |  |  |  |
6.625% Senior Unsecured Notes Due 2027 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 6.625% |  |  |  |  | 6.625% | 6.625%
Senior Notes, Principal amount |  | $ 500,000 |  |  |  |  | $ 416,791 | $ 416,791
Unamortized Debt Issuance Expense |  |  |  |  |  |  | 3,949 | 4,725
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  | $ 412,842 | $ 412,066
Proceeds from Senior Unsecured Notes, Net of debt issuance costs |  | 492,100 |  |  |  |  |  |
Senior Notes Debt Issuance Costs |  | $ 7,900 |  |  |  |  |  |
6.5% Senior Unsecured Notes Due 2028 [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage | 6.50% |  |  |  |  |  | 6.50% | 6.50%
Senior Notes, Principal amount | $ 400,000 |  |  |  |  |  | $ 400,000 | $ 0
Unamortized Debt Issuance Expense |  |  |  |  |  |  | 6,679 | 0
Unsecured Long-term Debt, Noncurrent |  |  |  |  |  |  | 393,321 | 0
Proceeds from Senior Unsecured Notes, Net of debt issuance costs | 392,800 |  |  |  |  |  |  |
Senior Notes Debt Issuance Costs | $ 7,200 |  |  |  |  |  |  |
Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  |  |  |  |  | 1,689,913 | 1,674,581
Unamortized Debt Issuance Expense |  |  |  |  |  |  | $ 16,461 | $ 13,918

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