Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock.

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- Definition

Increase in common stock available for issuance.

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- Definition

Number of shares issued under employee stock purchase plans.

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- Definition

Share based compensation arrangement by share based payment award number of shares available for issuance.

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- Definition

Share based compensation arrangement by share based payment award options grant date fair value.

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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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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

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

Net number of non-option equity instruments granted to participants.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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- Definition

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

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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

Number of options outstanding, including both vested and non-vested options.

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- Definition

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

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Share-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Mar. 12, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Aug. 09, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding		9,619,158		9,619,158			10,544,270
Share based compensation expense		$ 4,551	$ 3,709	$ 12,079	$ 9,932
Intrinsic value of Stock options exercised				14,900	8,200
Unrecognized compensation cost		$ 36,300		$ 36,300
Weighted-average period for recognition of compensation cost				2 years 7 months 6 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSU outstanding		797,147		797,147
Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross				825,572
Share Based Compensation Arrangement By Share Based Payment Award Options Grant Date Fair Value				$ 9,400
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation expense				$ 300	$ 300
2006 and 2015 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding		3,239,029		3,239,029
Remaining shares available to be granted		0		0
2019 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding		6,380,129		6,380,129
Number of shares available for issuance	4,750,000	4,153,915		4,153,915
Number of shares available to be issued		1,726,045		1,726,045
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock	4.00%
2019 Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSU outstanding		797,147		797,147
2019 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining shares available to be granted	525,000	1,310,363		1,310,363
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock	1.00%
Increase in common stock available for issuance		1,038,478		1,038,478
Purchase of common stock through payroll deductions expressed in percentage of fair market value	85.00%
Total number of shares issued under 2019 ESPP		253,115		253,115
2019 ESPP \| ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum shares allowed to be issued under ESPP	5,250,000
Inducement Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for issuance						3,000,000