Additional number of common shares reserved for future issuance.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
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-SubTopic 10
-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Balance Type:	na
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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.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Balance Type:	na
Period Type:	instant

- Definition

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

+ References

+ Details

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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.

+ References

+ Details

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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.

+ Details

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- Details

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- Details

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Stock-Based Compensation (Details) - USD ($)	3 Months Ended
Stock-Based Compensation (Details) - USD ($)	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Jun. 30, 2015
Stock Based Compensation
Shares granted	4,140,000
2015 Plan
Stock Based Compensation
Shares reserved for issuance				3,451,495
Additional shares reserved for issuance				9,890,310
Performance-based awards
Stock Based Compensation
Stock-based compensation expense	$ 1,400,000	$ 200,000
Employee and non-employee stock options
Stock Based Compensation
Stock-based compensation expense	$ 7,417,000	$ 4,051,000
Shares available for issuance	5,120,000		6,416,000
Restricted stock units
Stock Based Compensation
Number of shares vested	291,000
Shares granted	2,071,000
2015 Employee Stock Purchase Plan
Stock Based Compensation
Shares reserved for issuance	893,548
Shares granted	0
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 employee contribution of employee's cash compensation (as a percent)	15.00%
2015 Employee Stock Purchase Plan \| Minimum
Stock Based Compensation
Shares reserved for issuance	880,000