Debt Instruments - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
Dec. 09, 2015 |
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| Debt Instrument [Line Items] | |||
| Unamortized discount and deferred issuance costs | $ (66,590) | $ (71,986) | |
| Long-term debt, net | 278,410 | 273,014 | |
| Convertible debt | 1.75% convertible senior notes due 2020 | |||
| Debt Instrument [Line Items] | |||
| 1.75% convertible senior notes due 2020 | $ 345,000 | $ 345,000 | |
| Interest rate | 1.75% | 1.75% |
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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 of unamortized debt discount (premium) and debt issuance costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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/presentationRef
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