The maximum value of award or purchase a plan participant can receive under the plan per period.

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- Definition

Describes the expected annual number of plan offering periods as determined by the compensation committee.

+ References

No definition available.

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Describes the maximum term of the offering period as determined by the compensation committee.

+ References

No definition available.

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Describes the expected term of the offering period as determined by the compensation committee.

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No definition available.

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- Definition

The floor for the equity price in relation to the fair market value of common stock on the date of grant or offering, represented as a percentage.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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- Definition

Aggregate number of common shares reserved for future issuance.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
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- Definition

The cash inflow associated with the amount received from the stock plan during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

+ References

No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (a)(3)
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Stock-Based Compensation (Details)	1 Months Ended		5 Months Ended	6 Months Ended	12 Months Ended
Stock-Based Compensation (Details)	Dec. 31, 2018 USD ($) shares	Jun. 30, 2015 shares	Apr. 30, 2016 USD ($) shares	Oct. 31, 2016 USD ($) shares	Dec. 31, 2018 USD ($) period shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($)	Jun. 30, 2017 shares
Stock Based Compensation
Stock option shares approved								425,000
2015 Plan
Stock Based Compensation
Shares reserved for issuance	14,584,892	3,451,495			14,584,892
Shares reserved for issuance as a proportion common stock outstanding (as a percent)					4.00%
2015 Plan \| Minimum
Stock Based Compensation
Shares reserved for issuance	3,500,000				3,500,000
Employee stock purchase plan
Stock Based Compensation
Shares reserved for issuance	1,285,851	893,548			1,285,851
Shares reserved for issuance as a proportion common stock outstanding (as a percent)					1.00%
Price in relation to fair market value of common stock on the date of grant, lower range limit (as a percent)					85.00%
Maximum number of shares a participant may receive during the period (in shares)					5,000
Maximum amount of award or purchase during a calendar year \| $					$ 25,000
Maximum offering period, term					27 months
Number of expected offering periods each year \| period					2
Offering period, expected term					6 months
Issuance of common stock under employee stock purchase plan (in shares)			206,447	184,825
Proceeds from issuance of common stock under employee stock purchase plan \| $			$ 1,900,000	$ 1,700,000
Maximum employee contribution of employee's cash compensation (as a percent)	15.00%				15.00%
Employee stock purchase plan \| Minimum
Stock Based Compensation
Shares reserved for issuance	880,000				880,000
Performance-based awards
Stock Based Compensation
Stock option shares approved	600,000				600,000			200,000
Stock-based compensation expense \| $	$ 0
Employee and non-employee stock options
Stock Based Compensation
Stock-based compensation expense \| $					$ 14,198,000	$ 11,402,000	$ 10,601,000
Shares available for issuance	5,431,000				5,431,000	4,737,000
Employee and non-employee stock options \| 2015 Plan
Stock Based Compensation
Vesting period					4 years
Expiration period		10 years
Stock appreciation rights \| 2015 Plan
Stock Based Compensation
Vesting period					4 years
Expiration period					10 years
Restricted stock units
Stock Based Compensation
Shares granted					953