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Fair Value Measurements (Details) - USD ($) | Mar. 31, 2021 | Dec. 31, 2020 | Aug. 31, 2020
--- | --- | --- | ---
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | $ 268,384,000 | $ 294,695,000 |
Fair value of financial assets amount outstanding | 0 | 0 |
2025 Notes |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | 300,341,000 | 316,863,000 | $ 282,600,000
2025 Notes | Fair Value, Inputs, Level 2 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | 266,500,000 | 279,300,000 |
Fair value | 282,400,000 | 200,300,000 |
2017 Credit Facility | Credit Facility |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | $ 0 | $ 13,126,000 |

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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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