Represents the annual increase in shares authorized for issuance, effective January 1, 2018, as a percent.

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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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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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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. 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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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for 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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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Expected term of 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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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. 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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Number of share options (or share units) exercised during the current period.

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Equity Incentive Plans (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 20, 2017	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024	Jul. 02, 2024	Jun. 16, 2023	Jun. 16, 2022
Options
Outstanding balance at the beginning of the period (in shares)				6,416,744
Granted (in shares)				0
Exercised (in shares)				(6,667)
Forfeited (in shares)				(1,378,104)
Outstanding balance at the end of the period (in shares)		5,031,973		5,031,973		6,416,744
Options exercisable at the end of the period (in shares)		3,639,701		3,639,701
Options vested and expected to vest at end of period (in shares)		5,031,973		5,031,973
Weighted Average Exercise Price Per Share
Outstanding balance at the beginning of the period (in dollars per share)				$ 8.43
Exercised (in dollars per share)				2.4
Forfeited (in dollars per share)				7.55
Outstanding balance at the end of the period (in dollars per share)		$ 8.68		8.68		$ 8.43
Options exercisable at the end of the period (in dollars per share)		10.98		10.98
Options vested and expected to vest at end of the period (in dollars per share)		$ 8.68		$ 8.68
Weighted Average Remaining Life in Years
Outstanding balance				6 years		8 years 5 months 4 days
Options exercisable at end of period				4 years 11 months 8 days
Options vested and expected to vest at end of the period				6 years
Aggregate Intrinsic Value
Outstanding balance						$ 1,937
Assumptions used to determine grant-date fair value
Expected volatility					92.84%
Weighted average risk-free interest rate					4.00%
Expected dividend yield				0.00%	0.00%
Expected term (in years)					6 years 5 months 8 days
Expiration period				10 years
Unrecognized compensation cost related to non-vested stock options		$ 2,205		$ 2,205
Weighted average period for recognition of compensation cost				1 year 6 months 14 days
Minimum
Assumptions used to determine grant-date fair value
Vesting period				3 years
Maximum
Assumptions used to determine grant-date fair value
Vesting period				4 years
Options to purchase common stock
Weighted Average Exercise Price Per Share
Granted (in dollars per share)					$ 2.12
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Non vested, Weighted Average Grant Date Fair Value
Stock Based Compensation Expense		1,489	$ 1,370	$ 2,693	$ 2,618
Options to purchase common stock \| Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Non vested, Weighted Average Grant Date Fair Value
Stock Based Compensation Expense		387	729	1,021	1,356
Options to purchase common stock \| General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Non vested, Weighted Average Grant Date Fair Value
Stock Based Compensation Expense		476	$ 641	1,046	$ 1,262
Options to purchase common stock \| Restructuring charges
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Non vested, Weighted Average Grant Date Fair Value
Stock Based Compensation Expense		$ 626		$ 626
Restricted stock units to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Vested (in shares)				(220,000)
Outstanding at the end		0		0
2016 Plan
Assumptions used to determine grant-date fair value
Annual increase in authorized shares (as a percent)	4.00%
2016 Plan \| Restricted stock units to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at the beginning				220,000
Vested (in shares)				(220,000)
Outstanding at the end						220,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Non vested, Weighted Average Grant Date Fair Value
Outstanding at beginning( in dollars per share)				$ 19.4
Vested(in dollars per share)				$ 19.4
Outstanding at end(in dollars per share)						$ 19.4
2022 Plan
Assumptions used to determine grant-date fair value
Number of options or stock awards available for grant under the Plan									750,000
Common shares reserved for issuance							2,000,000	2,250,000
2016 and 2022 Plan
Assumptions used to determine grant-date fair value
Number of options or stock awards available for grant under the Plan		3,922,812		3,922,812