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Debt and Credit Facility - Additional Information (Details) - USD ($) |  | 3 Months Ended | 6 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
May 21, 2021 | Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | May 20, 2021 | Dec. 31, 2020 | May 01, 2020 | Apr. 28, 2020 | Nov. 26, 2019
Debt Instrument |  |  |  |  |  |  |  |  |  |
Loss on extinguishment of debt |  | $ (35,900,000) |  | $ (35,900,000) |  |  |  |  |  |
Interest expense capitalized |  | 300,000 | $ 200,000 | 400,000 | $ 500,000 |  |  |  |  |
Revolving Credit Facility |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  | $ 375,000,000.0 |  | $ 375,000,000.0 |  |  |  |  |  |
4.50% Senior Notes | Senior Notes |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Debt instrument contractual rate (percent) |  | 4.50% |  | 4.50% |  | 4.50% |  |  |  |
Debt issuance, percentage of principal amount |  |  |  |  |  | 100.00% |  |  |  |
Debt aggregate principal amount |  |  |  |  |  | $ 550,000,000.0 |  |  |  |
Unamortized debt issuance costs |  | $ 8,500,000 |  | $ 8,500,000 |  |  |  |  |  |
Interest expense |  | $ 2,900,000 |  | $ 2,900,000 |  |  |  |  |  |
Effective interest rate (percent) |  | 4.70% |  | 4.70% |  |  |  |  |  |
Debt instrument, payment terms |  |  |  | Interest accrues on the 4.50% Senior Notes beginning May 20, 2021 at a rate of 4.50% per annum and is payable semiannually on June 1 and December 1 of each year. The first interest payment date is December 1, 2021. |  |  |  |  |  |
Debt instrument, frequency of interest payment |  |  |  | semiannually |  |  |  |  |  |
Debt Instrument, first interest payment date |  |  |  | Dec. 01, 2021 |  |  |  |  |  |
Fair value of outstanding debt |  | $ 566,000,000.0 |  | $ 566,000,000.0 |  |  |  |  |  |
4.50% Senior Notes | Senior Notes | On or After June 1, 2026 |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Redemption price as percentage of principal (percent) |  |  |  | 102.25% |  |  |  |  |  |
4.50% Senior Notes | Senior Notes | On or After June 1, 2027 |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Redemption price as percentage of principal (percent) |  |  |  | 101.50% |  |  |  |  |  |
4.50% Senior Notes | Senior Notes | On or After June 1, 2028 |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Redemption price as percentage of principal (percent) |  |  |  | 100.75% |  |  |  |  |  |
4.50% Senior Notes | Senior Notes | On or After June 1, 2029 |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Redemption price as percentage of principal (percent) |  |  |  | 100.00% |  |  |  |  |  |
4.50% Senior Notes | Senior Notes | Prior to June 1, 2026 |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Redemption price as percentage of principal (percent) |  |  |  | 104.50% |  |  |  |  |  |
Percentage of principal that can be redeemed (percent) |  |  |  | 40.00% |  |  |  |  |  |
Senior Notes Due 2025 | Senior Notes |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Debt instrument contractual rate (percent) |  |  | 6.50% |  | 6.50% |  |  | 6.50% | 6.50% |
Debt issuance, percentage of principal amount |  |  |  |  |  |  |  | 101.00% | 100.00% |
Debt aggregate principal amount |  |  |  |  |  |  |  | $ 50,000,000.0 | $ 300,000,000.0 |
Unamortized debt issuance costs | $ 5,000,000.0 |  |  |  |  |  |  |  |  |
Interest expense |  | 3,200,000 | $ 4,200,000 | $ 9,200,000 | $ 4,200,000 |  |  |  |  |
Effective interest rate (percent) |  |  | 6.80% |  | 6.80% |  |  |  |  |
Fair value of outstanding debt |  |  |  |  |  |  | $ 376,800,000 |  |  |
Percentage of redemption price of principal amount | 108.83% |  |  |  |  |  |  |  |  |
Debt accrued and unpaid interest | $ 1,300,000 |  |  |  |  |  |  |  |  |
Loss on extinguishment of debt | (35,900,000) |  |  |  |  |  |  |  |  |
Premium payment | 30,900,000 |  |  |  |  |  |  |  |  |
Repayments of Senior Debt | $ 382,200,000 |  |  |  |  |  |  |  |  |
Senior Notes Due 2028 | Senior Notes |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Debt instrument contractual rate (percent) |  |  |  |  |  |  |  |  |  | 4.625%
Debt issuance, percentage of principal amount |  |  |  |  |  |  |  |  |  | 100.00%
Debt aggregate principal amount |  |  |  |  |  |  |  |  |  | $ 500,000,000.0
Unamortized debt issuance costs |  | 6,000,000.0 |  | 6,000,000.0 |  |  |  |  |  |
Interest expense |  | $ 6,000,000.0 | $ 6,000,000.0 | $ 12,000,000.0 | $ 12,000,000.0 |  |  |  |  |
Effective interest rate (percent) |  | 4.80% |  | 4.80% |  |  |  |  |  |
Fair value of outstanding debt |  | $ 516,200,000 |  | $ 516,200,000 |  |  | $ 521,300,000 |  |  |

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