Convertible Senior Notes (Details) $ in Thousands |
3 Months Ended | 12 Months Ended |
|---|---|---|
|
Mar. 31, 2018
USD ($)
|
Dec. 31, 2017
USD ($)
|
|
| Debt Instrument, Redemption [Line Items] | ||
| Proceeds from convertible senior notes | $ 282,185 | |
| Convertible senior notes maturity date | Jan. 15, 2022 | |
| Convertible senior notes conversion ratio | 0.0614698 | 0.0614698 |
| Convertible senior notes | $ 283,054 | $ 282,827 |
| Convertible Debt [Member] | ||
| Debt Instrument, Redemption [Line Items] | ||
| Convertible senior notes aggregate principal amount | $ 287,500 | |
| Convertible senior notes interest rate per annum | 6.25% |
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Face (par) amount of debt instrument at time of issuance. 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 Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. 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 The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt. No definition available.
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- Details
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