Subsequent Events (Details) - Subsequent Event $ / shares in Units, $ in Thousands	Jul. 23, 2018 USD ($) $ / shares shares
Subsequent Event [Line Items]
Gross proceeds from issuance of convertible debt	$ 143,750
Proceeds from issuance of convertible debt, net of underwriting discounts	$ 139,438
1.75% Convertible Senior Notes due 2023
Subsequent Event [Line Items]
Stated interest rate	1.75%
Debt instrument, redemption price, percentage	100.00%
Debt instrument, convertible, conversion ratio	0.0327332
Debt instrument, convertible, conversion price (in dollars per share) \| $ / shares	$ 30.55
Premium percentage of conversion price	30.00%
Public Offerings
Subsequent Event [Line Items]
Shares sold in offering (in shares) \| shares	4,836,336
Offering price (in dollars per share) \| $ / shares	$ 23.50
Gross proceeds received from stock offering	$ 113,654
Proceeds received from stock offering, net of underwriting discount	$ 107,971

Debt Instrument, Convertible, Premium Percentage of Conversion Price

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- Definition

Proceeds from Issuance of Convertible Debt, Net of Underwriting Discounts

+ References

No definition available.

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- Definition

Sale of Stock, Gross Proceeds Received on Transaction

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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-Publisher FASB
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-SubTopic 20
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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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