Number of shares increased annually to common stock shares reserved for issuance.

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- Definition

Share based compensation arrangement by share based payment award approval date.

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Share based compensation arrangement by share based payment award expiration year.

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- Definition

Share based compensation arrangement by share based payment award number of shares authorized for employee stock purchase plan.

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No definition available.

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- Definition

Share based compensation arrangement increase in number of shares reserved for issuance percentage under plan.

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No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for statutory payroll taxes incurred through that date and withheld from employees pertaining to services received from them, including entity's matching share of the employees FICA taxes and contributions to the state and federal unemployment insurance programs. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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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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

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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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

Description of terms of award under share-based payment arrangement.

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- Definition

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

+ 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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The increase (decrease) during the period in the number of shares issued.

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Preferred Stock, Common Stock and Stockholders' Equity - Employee Stock Purchase Plan and Stock-Based Compensation - Additional Information (Detail) - USD ($)		1 Months Ended		12 Months Ended
	Jan. 01, 2022	May 31, 2017	Jun. 30, 2013	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2018	Apr. 26, 2018	Apr. 30, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation costs				$ 2,900,000
Weighted average period				1 year 3 months 25 days
Aggregate number of shares of common stock reserved under the plan				8,501,391	7,566,145		6,286,425
Shares of common stock available for future issuance under ESPP				344,574	244,574
Stock issued during period, shares, period increase						620,000
Issuance of common stock under employee stock purchase plan				0	118,491
Payroll withholdings from employees					$ 119,000
Amended and Restated ESPP [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate number of shares of common stock reserved under the plan		1,250,000
Number of shares increased annually to common stock shares reserved for issuance		100,000						30,000
Award plan expiration year		2027
Employee stock purchase plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of common stock as percentage of fair market value			85.00%
Percentage of deduction of eligible compensation			20.00%
Aggregate number of shares of common stock reserved under the plan			30,000
Shares available for issuance, description				In addition, the number of shares of common stock available for issuance under the ESPP has been annually increased on the first day of each fiscal year during the term of the ESPP by an amount equal to the lesser of: (i) 30,000 shares; (ii) one percent of the outstanding shares of common stock as of the last day of the immediately preceding fiscal year; or (iii) such other amount as the Company’s board of directors may determine.
Reserve percentage for issuance of shares			1.00%
ESPP approval date			Aug. 29, 2013
Subsequent Event \| Employee stock purchase plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate number of shares of common stock reserved under the plan	444,574
Stock issued during period, shares, period increase	100,000