Debt Instrument, Convertible, Premium Percentage of Conversion Price

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- Definition

Debt Issuance Costs, Gross, Carrying Amount of Equity Component

+ References

No definition available.

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- Definition

Debt Issuance Costs, Gross, Carrying Amount of Liability Component

+ References

No definition available.

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- Definition

Proceeds from Issuance of Convertible Debt, Net of Underwriting Discounts

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

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

+ References

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-Publisher FASB
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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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+ Details

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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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.

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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

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

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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.

+ References

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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

No definition available.

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Convertible Senior Notes - Narrative (Details)		12 Months Ended
Convertible Senior Notes - Narrative (Details)	Jul. 23, 2018 USD ($) $ / shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Proceeds from convertible debt		$ 138,953,000	$ 0	$ 0
Proceeds from issuance of convertible debt, net of underwriting discounts	$ 138,953,000
Debt issuance costs, gross	4,797,000
Debt issuance costs, gross, carrying amount of liability component	3,832,000
Debt issuance costs, gross, carrying amount of equity component	965,000
1.75% Convertible Senior Notes due 2023
Debt Instrument [Line Items]
Proceeds from convertible debt	143,750,000
Proceeds from issuance of convertible debt, net of underwriting discounts	$ 138,953,000
Stated interest rate	1.75%
Debt instrument, redemption price, percentage	100.00%
Convertible conversion ratio	0.0327332
Debt instrument, convertible, conversion price (in dollars per share) \| $ / shares	$ 30.55
Debt instrument, convertible, premium percentage of conversion price	30.00%
Debt issuance costs, gross, carrying amount of equity component		965,000
Public Offering
Debt Instrument [Line Items]
Share price (in dollars per share) \| $ / shares	$ 23.50
Fair Value, Inputs, Level 2 \| 1.75% Convertible Senior Notes due 2023
Debt Instrument [Line Items]
Debt instrument, fair value		$ 117,875,000