Employee stock purchase plan description.

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Percentage of discount on purchase price of common stock.

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

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

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

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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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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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Number of new stock issued during the period.

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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands			12 Months Ended
	Jun. 18, 2021	Jun. 05, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jun. 14, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 9,207	$ 10,850	$ 9,885
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			8,441	9,557	7,887
Unrecognized compensation cost related to non-vested stock options expected to be recognized			$ 11,100
Unrecognized compensation expense related to non-vested stock options, weighted-average period of recognition			1 year 8 months 15 days
Total intrinsic value of stock options exercised			$ 200	1,500
Stock options granted, contractual term			10 years
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 616	1,017	566
Unrecognized compensation expense related to non-vested stock options, weighted-average period of recognition			2 years 18 days
Total fair value of stock awards vested			$ 600	1,000	600
Unrecognized cost related to non-vested restricted stock awards			$ 3,100
Maximum \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted, vesting period			4 years
Maximum \| Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance						1,000,000
Minimum \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted, vesting period			2 years
2017, 2013, 2007 and 2004 Plans \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock options authorized grant			16,000,000
2017 Omnibus Incentive Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in stock available for issuance under plan	5,000,000	500,000
2017 Plans \| Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			1,000,000
Stock-based compensation expense			$ 200	$ 300	$ 300
Percentage of discount on purchase price of common stock			15.00%
Employee stock purchase plan, description			Under the ESPP, shares of the Company’s common stock may be purchased at a discount (15%) of the lesser of the closing price of the Company’s common stock on the first trading or the last trading day of the offering period. The current offering period extends from December 1, 2021 to May 31, 2022. The Company expects to offer six-month offering periods after the current period
Shares of common stock issued			81,557	50,827	60,825