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

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Aggregate number of common shares reserved for future issuance.

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

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

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Other than shares newly issued, the number of additional shares issued (for example, a stock split) or canceled (for example, to correct a share issuance), during the period under the plan.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Percentage of vesting of award under share-based payment arrangement.

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

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Equity Incentive Plan (Details) - USD ($) $ in Thousands			3 Months Ended
Equity Incentive Plan (Details) - USD ($) $ in Thousands	Feb. 12, 2021	Feb. 03, 2021	Mar. 31, 2022	Mar. 31, 2021	Jan. 01, 2022	Feb. 05, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for issuance					1,728,326
Share-based Payment Arrangement, Expense			$ 1,976	$ 1,593
2017 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period of incentive plan			10 years
Vesting period			4 years
2017 Plan [Member] \| Share-based Payment Arrangement, Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage			25.00%
2017 Plan [Member] \| Share-based Payment Arrangement, Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
2017 Plan [Member] \| Person Possessing Less than 10% of Voting Power [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum percent of fair market value of common stock			100.00%
2017 Plan [Member] \| Person Possessing More than 10% of Voting Power [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum percent of fair market value of common stock			110.00%
Expiration period of incentive plan			5 years
2017 Plan [Member] \| Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation outstanding shares						10,567,508
2017 Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation outstanding shares						163,157
2015 Plan [Member] \| Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation outstanding shares						2,303,309
2015 Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation outstanding shares						35,561
2021 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum percent of fair market value of common stock		100.00%
Common stock, number of shares reserved		4,264,341
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum			4.00%
Number of shares available for issuance			1,347,961
2021 Inducement Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period of incentive plan	10 years
2021 Employee Stock Purchase Plan Member
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, number of shares reserved			430,551
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum			1.00%
Share-based Compensation Arrangement by Share-based Payment Award, Other Share Increase (Decrease)			430,551
Share-based Payment Arrangement, Expense			$ 16