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Unsecured Convertible Senior Notes - Net Proceeds (Details) - USD ($) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Nov. 15, 2018 | Dec. 31, 2020 | Dec. 31, 2018
Debt Instrument |  |  |
Issuance costs |  | $ (6,785) | $ (6,800)
2023 Convertible Senior Notes |  |  |
Debt Instrument |  |  |
2023 Notes principal amount issued | $ 210,000 |  |
Repayment of previously outstanding loan | (146,046) |  |
Purchase of Capped Call | (33,180) |  |
Issuance costs | (6,800) |  |
Net proceeds available for corporate use | $ 23,974 |  |

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- Definition The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, net of issuance costs, loan repayments, and other purchases. + References No definition available. + Details
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- Definition Represents the purchase of a capped call transaction, which will cover the number of shares of common stock underlying the Convertible Notes when the common stock is trading between a specified conversion price range. + References No definition available. + Details
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- Definition The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585 + Details
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- Definition The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585 + Details
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- Definition The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585 + Details
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