Employee stock purchase plan description.

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

+ References

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- Definition

Discount rate from fair value on offering date that participants pay for shares.

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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

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

+ References

No definition available.

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- Definition

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

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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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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands			3 Months Ended
	Apr. 26, 2021	May 23, 2019	Mar. 31, 2021	Mar. 31, 2020	Jun. 14, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 2,280	$ 2,331
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			2,205	1,864
Unrecognized compensation cost related to non-vested stock options expected to be recognized			$ 16,500
Unrecognized compensation expense related to non-vested stock options, weighted-average period of recognition			1 year 9 months 18 days
Total intrinsic value of stock options exercised			$ 200	800
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 29	$ 397
Unrecognized compensation expense related to non-vested stock options, weighted-average period of recognition			1 year 4 months 24 days
Shares granted to employees			0	0
Unrecognized cost related to non-vested restricted stock awards			$ 300
Maximum \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 100
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
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 \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in stock available for issuance under plan	5,000,000
2017 Omnibus Incentive Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in stock available for issuance under plan		3,500,000
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			$ 100	$ 100
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, 2020 to May 31, 2021. The Company expects to offer six-month offering periods after the current period.