Employee Stock Purchase Plan Contribution Percentage

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- Definition

Employee Stock Purchase Plan Offering Period

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- Definition

Employee Stock Purchase Plan Purchase Period

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- Definition

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

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Aggregate number of common shares reserved for future issuance.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

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 tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

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

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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.

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No definition available.

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- Definition

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

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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

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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- Definition

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

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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- Definition

Number of grantees affected by modification of award 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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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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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-based Compensation - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Jul. 31, 2013	Dec. 31, 2020 USD ($) employee $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value per share (in dollars per share) \| $ / shares		$ 18.89	$ 12.99	$ 4.78
Aggregate intrinsic value for options exercised		$ 80,600,000	$ 19,900,000	$ 2,200,000
Fair value of options vested		14,500,000	6,300,000	6,800,000
Tax benefit recognized related to share-based compensation cost		0
Total share-based compensation expense		19,374,000	17,458,000	11,475,000
Share-based Payment Arrangement, Plan Modification, Incremental Cost		$ 4,700,000
Share-based Payment Arrangement, Plan Modification, Number of Grantees Affected \| employee		10
2004 Stock Option Plan and 2013 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under the Plans (in shares) \| shares		11,835,327
Stock options grant period, years		10 years
Stock options vesting period and exercisable period, years		4 years
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total value of shares vested		$ 12,500,000	$ 17,600,000	$ 1,000,000.0
Shares vested (in shares) \| shares		455,278
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Length of offering period, in months	12 months
Length of purchase periods, in months	6 months
Purchase price percentage of fair market value of shares	85.00%
Shares issued (in shares) \| shares		89,477	203,464	257,132
Total share-based compensation expense		$ 900,000	$ 800,000	$ 700,000
Common stock reserved for issuance (in shares) \| shares		1,642,147
Share available for grant (in shares) \| shares		536,443
ESPP \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contribution percentage of purchase shares on participants eligible compensation	0.00%
ESPP \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contribution percentage of purchase shares on participants eligible compensation	10.00%
Service component
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 26,200,000
Unrecognized compensation cost, weighted-average recognized period		2 years 25 days
Service and Performance components
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 7,100,000
Unrecognized compensation cost, weighted-average recognized period		1 year 8 months 1 day