Convertible Notes - Carrying and fair value (Details) - Convertible Notes $ in Thousands	Dec. 31, 2018 USD ($)
Convertible Notes
Par value of the Convertible Notes	$ 201,250
Unamortized debt discounts	(45,058)
Unamortized debt issuance costs	(4,522)
Net carrying value of Convertible Notes	151,670
Fair value of Convertible Notes	$ 169,970

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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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.

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Amount, after accumulated amortization, of debt discount.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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