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- Definition

Employee Stock Ownership Plan, Purchase Period

+ References

No definition available.

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- Definition

Employee Stock Ownership Plan, Purchase Price, Percent

+ References

No definition available.

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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.

+ References

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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 nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

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

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- Definition

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

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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.

+ References

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- Definition

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

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- Definition

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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- Definition

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

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- Definition

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

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- Definition

Number of share options (or share units) exercised during the current period.

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Stock-based Compensation - Narrative (Details)	1 Months Ended	3 Months Ended				9 Months Ended		12 Months Ended	53 Months Ended
Stock-based Compensation - Narrative (Details)	Apr. 30, 2021 shares	Sep. 30, 2025 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Jun. 30, 2024 shares	Mar. 31, 2024 shares	Sep. 30, 2025 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Dec. 31, 2021	Sep. 30, 2025 USD ($) shares
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Weighted-average grant date fair value of awards (in usd per share) \| $ / shares		$ 0.81	$ 1.76			$ 1.16	$ 3.57
Stock option exercises (in shares)		0				0
Aggregate intrinsic fair value of options exercised \| $			$ 0				$ 0
Share-based compensation expense not yet recognized \| $		$ 6,600,000				$ 6,600,000			$ 6,600,000
Inducement Stock Option
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Options granted (shares)						201,720	0
Shares reserved for vesting of restricted stock units \| 2021 Stock Incentive Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Granted (in shares)						0
Vested (in shares) \| $			$ 0				$ 700,000
Shares reserved for issuance under the 2021 Stock Incentive Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Options granted (shares)						3,390,691
Stock option exercises (in shares)						0
Share-based compensation not yet recognized, recognition period						2 years
2021 Stock Incentive Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Maximum number of shares to be added annually, as a percentage of outstanding shares (percent)	5.00%
2021 Stock Incentive Plan \| Common stock to be issued upon exercise of the K2HV Loan Agreement conversion feature
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Common stock authorized to be issued (in shares)	477,725
2021 Stock Incentive Plan \| Shares reserved for vesting of restricted stock units
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense not yet recognized, excluding option \| $		$ 0				$ 0			$ 0
2021 Stock Employee Stock Purchase Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Offering period								6 months
Purchase period								6 months
ESPP purchase price, percent								0.85
Common Stock
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Common stock authorized to be issued (in shares)	3,352,725
Stock option exercises (in shares)			11,125	100	5,999
Common Stock \| 2021 Stock Incentive Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Common stock authorized to be issued (in shares)	2,843,116
Maximum number of shares to be added annually, as a percentage of outstanding shares (in shares)									7,152,859
Shares purchased by employees (in shares)						39,853	35,180
Common Stock \| 2017 Stock Incentive Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Common stock authorized to be issued (in shares)	31,884