Convertible Debt - Components of Notes (Details) $ in Thousands	Mar. 31, 2018 USD ($)
Liability component:
Net carrying amount	$ 106,574
Equity component	32,643
Convertible Debt
Liability component:
Convertible senior notes	143,750
Less: debt discount, net of amortization	$ (37,176)

No definition available.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

+ References

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-Publisher FASB
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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