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Fair Value Measurements (Details) - USD ($) | Sep. 30, 2020 | Aug. 04, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | $ 291,314,000 |  | $ 399,579,000
Fair value of financial assets amount outstanding | 0 |  | 0
2021 Notes |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | 12,655,000 |  | 400,000,000
2021 Notes | Fair Value, Inputs, Level 2 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | 12,700,000 |  | 397,500,000
Fair value | 11,800,000 |  | 354,000,000.0
2025 Notes |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | 315,489,000 | $ 282,600,000 | 0
2025 Notes | Fair Value, Inputs, Level 2 |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | 276,100,000 |  |
Fair value | 255,500,000 |  |
2017 Credit Facility | Credit Facility |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Carrying value | $ 0 |  | $ 0

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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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