Employee share purchase plan offering period.

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- Definition

Employee share purchase plan second offering period.

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- Definition

Fair market value percentage available to employees.

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- Definition

Increase in number of common stock shares available for issuance.

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No definition available.

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- Definition

Maximum number of shares permitted to acquire through payroll.

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No definition available.

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- Definition

Maximum percentage of base compensation permitted to acquire common stock through payroll.

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No definition available.

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- Definition

Maximum values of shares permitted to acquire through payroll.

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No definition available.

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- Definition

Percentage of minimum stock held by employee to determine exercise price of options on date of grant.

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No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award, options, exercise price, percent of estimated fair value.

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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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 option 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 estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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

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

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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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

Weighted average grant-date fair value of options vested.

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- Definition

Number of new stock issued during the period.

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Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jan. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend rate		0.00%	0.00%
Common stock, shares reserved for issuance		5,173,757	4,325,988
Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend rate		0.00%
2016 Incentive Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options term		10 years
Options and restricted stock awards vesting period		4 years
Aggregate intrinsic value of options vested and expected to vest		$ 2,200,000	$ 1,900,000
Aggregate intrinsic value of options exercised			$ 800,000
Weighted average grant-date fair value of options granted		$ 3.66	$ 9.62
Unrecognized stock-based compensation expense		$ 9,600,000
Unrecognized stock-based compensation expense, weighted-average recognition period		2 years 2 months 12 days
Fair value of options vested		$ 5,300,000	$ 4,000,000.0
2016 Incentive Award Plan \| Incentive Stock Options \| 10% Stockholder
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated fair value shares date of grant, maximum		10.00%
2016 Incentive Award Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price, percent of estimated fair value of shares on date of grant		100.00%
2016 Incentive Award Plan \| Minimum \| Incentive Stock Options \| 10% Stockholder
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price, percent of estimated fair value of shares on date of grant		110.00%
2016 Incentive Award Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate intrinsic value of options exercised		$ 100,000
2016 Incentive Award Plan \| Maximum \| 10% Stockholder
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options term		5 years
2019 Incentive Award Plan \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in number of common stock shares available for Issuance	1,261,822
2019 Employee Share Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense, weighted-average recognition period		6 months
Expected dividend rate		0.00%	0.00%
Common stock, shares reserved for issuance		477,276		160,000
Maximum percentage of base compensation permitted to acquire common stock through payroll		15.00%
Maximum number of shares permitted to acquire through payroll		50,000
Maximum values of shares permitted to acquire through payroll		$ 25,000
Fair market value percentage available to employees		85.00%
Employee share purchase plan offering period		6 months 15 days
Employee share purchase plan second offering period		5 months 15 days
Shares issued in first offering period		16,147	14,766
2019 Employee Share Purchase Plan \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares reserved for issuance	315,455
2019 Employee Share Purchase Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense		$ 100,000