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.

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No definition available.

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

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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

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

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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- Definition

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

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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.

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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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- Definition

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

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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.

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No definition available.

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- Definition

Number of shares purchased for issuance under share-based payment arrangement.

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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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Stock-Based Compensation (Details)	6 Months Ended				12 Months Ended
Stock-Based Compensation (Details)	Oct. 31, 2020 USD ($) shares	Apr. 30, 2020 USD ($) shares	Oct. 31, 2019 USD ($) shares	Apr. 30, 2019 USD ($) shares	Dec. 31, 2020 USD ($) period shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)	Jun. 30, 2015 shares
Stock Based Compensation
Shares granted					6,204,000
2015 Plan
Stock Based Compensation
Shares reserved for issuance					13,988,187			3,451,495
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
Employee stock purchase plan
Stock Based Compensation
Shares reserved for issuance					2,184,963			893,548
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
Number of Shares Purchased	136,288	97,247	136,084	132,177
Total Proceeds \| $	$ 4,052,000	$ 3,061,000	$ 2,176,000	$ 2,147,000
Maximum employee contribution of employee's cash compensation (as a percent)					15.00%
Employee stock purchase plan \| Minimum
Stock Based Compensation
Shares reserved for issuance					880,000
Performance-based awards
Stock Based Compensation
Stock-based compensation expense \| $					$ 17,200,000	$ 7,300,000
Employee and non-employee stock options
Stock Based Compensation
Stock-based compensation expense \| $					$ 50,171,000	$ 28,624,000	$ 14,198,000
Shares available for issuance					3,466,000	6,416,000
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
Expiration period					10 years
Restricted stock units
Stock Based Compensation
Number of shares vested					1,100
Shares granted					3,102