Debt - Summary of Net Carrying Amount of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Net carrying amount	$ 291,038	$ 288,967
Convertible Debt
Debt Instrument [Line Items]
Principal amount	300,000	300,000
Unamortized debt discount	(3,532)	(4,348)
Net carrying amount before unamortized debt issuance costs	296,468	295,652
Unamortized debt issuance costs	(5,430)	(6,685)
Net carrying amount	$ 291,038	$ 288,967

Long Term Debt, Net Of Unamortized Discount

No definition available.

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- Definition

Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

+ References

+ Details

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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.

+ References

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-Publisher FASB
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+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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-Publisher FASB
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Balance Type:	debit
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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.

+ References

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+ Details

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- Details

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