Employee stock purchase plan description.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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-Publisher FASB
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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.

+ References

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-Publisher FASB
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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

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

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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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- 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.

+ References

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-Name Accounting Standards Codification
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Stock-Based Compensation - Additional Information (Detail) - USD ($)			3 Months Ended		6 Months Ended
	Apr. 26, 2021	May 23, 2019	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Jun. 14, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 1,603,000	$ 2,444,000	$ 3,477,000	$ 4,678,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			1,321,000	2,341,000	2,924,000	4,500,000
Unrecognized compensation cost related to non-vested stock options expected to be recognized			10,200,000		$ 10,200,000
Unrecognized compensation expense related to non-vested stock options, weighted-average period of recognition					1 year 2 months 12 days
Total intrinsic value of stock options exercised					$ 0	200,000
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			245,000	57,000	$ 496,000	86,000
Unrecognized compensation expense related to non-vested stock options, weighted-average period of recognition					2 years 10 months 24 days
Total fair value of stock awards vested			200,000	100,000	$ 500,000	100,000
Unrecognized cost related to non-vested restricted stock awards			$ 2,400,000		$ 2,400,000
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		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	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		1,000,000
Stock-based compensation expense					$ 100,000	$ 100,000
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 June 1, 2022 to November 30, 2022. The Company expects to offer six-month offering periods after the current period.
2017 Plans \| Maximum \| Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 100,000	$ 100,000