Debt - Summary of convertible notes (Details) - Convertible debt - 3.00% Convertible senior notes due 2022 - USD ($) |
Dec. 31, 2018 |
Dec. 31, 2017 |
Aug. 31, 2015 |
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Long-term debt | |||
Principal | $ 150,000,000 | $ 150,000,000 | $ 150,000,000 |
Less: Debt issuance costs | (1,746,000) | (2,121,000) | |
Less: Debt discount, net | (35,054,000) | (42,572,000) | |
Net carrying amount | $ 113,200,000 | $ 105,307,000 |
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Definition Amount, after accumulated amortization, of debt discount. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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