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

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Excess of accrued right to purchase stock

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Maximum shares allowed to be issued.

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Share based compensation arrangement by share based payment award purchase price of common stock through payroll deductions percentage.

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Share based compensation arrangement by share based payment award stock offering period.

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Total compensation cost reversed

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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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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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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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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The cash inflow associated with the amount received from the stock plan during the period.

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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 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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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The excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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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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Number of options vested.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended			6 Months Ended
	Jan. 01, 2023	Mar. 31, 2018	Jun. 30, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate proceeds from shares issued under the plan						$ 150	$ 439
Stock-based compensation			$ 2,402	$ 3,143		$ 4,771	$ 7,194
Weighted-average grant date fair value per share for options granted						$ 1.01	$ 1.72
Share-Based Goods and Nonemployee Services Transaction, Modification of Terms, Incremental Compensation Cost						$ 400
Compensation cost, Total			$ 800			$ 800
Total compensation cost reversed					$ 100
2015 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option vesting period						4 years
Stock options expiration period						10 years
Number of additional shares available for future grant			0			0
2018 Incentive Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for issuance		3,186,205
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock	4.00%	4.00%
Maximum shares of common stock may be issued		20,887,347
Number of shares outstanding available for future grant	2,299,356		1,332,510			1,332,510
2018 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for issuance		353,980
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock	1.00%	1.00%
Number of shares outstanding available for future grant	574,839		2,234,938			2,234,938
Maximum shares allowed to be issued under ESPP		4,778,738
Purchase of common stock through payroll deductions expressed in percentage of fair market value						85.00%
Common stock offering period						6 months
Number of shares issued to the plan						116,332	147,871
Aggregate proceeds from shares issued under the plan						$ 200	$ 400
Stock-based compensation			$ 100	$ 100		100	$ 100
Excess of accrued right to purchase stock						25,000
2015 and 2018 Stock Incentive Plans
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense			$ 12,900			$ 12,900
Unrecognized compensation expense estimated to be recognized over period						2 years 6 months
OXB Solutions \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock award and exercise vested option to transferred employees						100,000
OXB Solutions \| Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of stock award and exercise vested option to transferred employees						1,600,000