Cumulative catch-up adjustment of stock-based compensation expense.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of noncash expense for share-based payment arrangement.

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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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

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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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Stock Plans and Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended		9 Months Ended
	Sep. 30, 2019	Dec. 31, 2017	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	May 31, 2019	May 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Shares reserved for issuance (in shares)					4,600,000	3,000,000	1,900,000
Weighted-average grant-date fair value of options granted			$ 11.01	$ 10.79
Total intrinsic value of options exercised			$ 2,000,000.0	$ 1,600,000
Stock-based compensation			18,106,000	14,049,000
Unrecognized stock-based compensation expense			$ 27,800,000
Unrecognized stock-based compensation expense expected to be recognized, term			1 year 9 months 18 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award
Total fair value of awards vested and settled			$ 6,200,000	3,600,000
Total intrinsic value of awards vested and settled			$ 3,900,000	$ 1,800,000
Granted			531,164
RSUs \| Executives
Share-based Compensation Arrangement by Share-based Payment Award
Granted	100,000	45,000	100,000
Total fair value of awards			$ 1,200,000
Cumulative catch-up adjustment of stock-based compensation expense			700,000
Stock-based compensation			$ 0
2018 ESPP
Share-based Compensation Arrangement by Share-based Payment Award
Number of common shares reserved for future issuance							400,000
Number of common stock purchased by employees			42,266	36,804