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Percentage Of Compensation Received.

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Amount of expense for employee benefit and equity-based compensation.

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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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Reflects the amount as of the balance sheet date of the employer's guarantee of debt repayment by the ESOP.

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The shares that, although not legally released, will be released by a future scheduled and committed debt service payment and will be allocated to employees for service rendered in the current accounting period. The ESOP documents typically define the period of service to which the shares relate. ESOP shares are released to compensate employees directly, to settle employer liabilities for other employee benefits, and to replace dividends on allocated shares that are used for debt service.

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Weighted average purchase price of capital shares purchased through an employee stock ownership plan.

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Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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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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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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Number of shares issued under share-based payment arrangement.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Number of shares of stock issued during the period pursuant to acquisitions.

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

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Stock-Based Compensation - Additional Information (Detail) $ / shares in Units, $ in Millions	1 Months Ended			12 Months Ended
	Jan. 31, 2025 shares	Oct. 31, 2024 USD ($)	Jan. 31, 2024 shares	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2025 USD ($) € / shares shares	Dec. 31, 2024 USD ($) $ / shares
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Weighted average grant-date fair value of options granted \| $ / shares				$ 1.37		$ 1.35
Research & development expense						$ 0.9
Stock options issued as replacement awards \| shares				1,546,258
Stock options [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock options issued as replacement awards \| shares				1,546,258
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share based payment arrangements, Equity instruments other than options granted \| shares				6,971,912
Stock-based compensation expenses				$ 0.3
Other Subsidiaries Equity Plan
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expenses				$ 0.1		0.2
Unrecognized stock based compensation compensation, Expected period of recognition				3 years 2 months 12 days
Total unrecognized stock-based compensation expense				$ 0.2
Restricted Stock [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expenses				0.5		1.8
Fair value of restricted stock units vested				0.8
HSOP Plan[Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expenses				0.0		0.1
Unrecognized stock based compensation compensation				$ 0.0	$ 0.0
Employee stock ownership plan, Number of shares available for future issuance \| shares				257,419	257,419
Employee stock ownership plan, Weighted average purchase price of shares \| € / shares					$ 0.06
Employee stock ownership plan, Employer loan guarantee				$ 0.5	$ 0.5
Percentage of per annum interest rate				2.00%
Share based payment arrangement, Shares issued in period \| shares				7,281,376
HSOP Plan[Member] \| Non Recourse Loan [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Employee stock ownership plan, Weighted average purchase price of shares \| € / shares					$ 0.06
Percentage of compensation received				2.00%
Percentage of per annum interest rate				2.00%
HSOP Plan[Member] \| HSOP Shares [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share based payment arrangements, Equity instruments other than options granted \| shares				0
Number of share options exercised during the current period \| shares				0
Two Thousand And Twenty Incentive Plan [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expenses		$ 3.2		$ 13.7		$ 23.5
Selling, General and Administrative Expense		1.2
Unrecognized stock based compensation compensation				$ 22.8	$ 22.8
Unrecognized stock based compensation compensation, Expected period of recognition				2 years 1 month 24 days
Number of options outstanding \| shares				0	0
Research & development expense		$ 2.0
Two Thousand And Twenty One Incentive Award Plan [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Shares reserved for future issuance \| shares				71,734,896	71,734,896
Number of options outstanding \| shares				31,145,683	31,145,683
Common stock, for issuance to executive officers \| shares	8,397,987		8,301,319