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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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Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

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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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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.

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

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Period from grant to expiration date of 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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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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Number of non-vested options outstanding.

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Number of options vested.

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Share-based compensation (Details) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
Share-based compensation (Details) - USD ($) $ in Millions	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Jun. 12, 2024	Jun. 11, 2020	Jun. 07, 2018
Share-Based Compensation
Aggregate common stock reserved for issuance	7,048,080
Share-based compensation arrangement by share based payment award percentage of fair market Person holding more then 10% voting stock	110.00%
Intrinsic value of options outstanding	$ 0.5		$ 10.0
Intrinsic value of options unvested	0.0		$ 0.2
Intrinsic value of options exercised	$ 9.5	$ 1.3
Tranche one
Share-Based Compensation
Option to purchase granted	136,652		68,490
Vesting on First Anniversary of Grant
Share-Based Compensation
Options unvested	216,309
Stock option vesting, percentage	50.00%
Vesting on Second Anniversary of Grant
Share-Based Compensation
Stock option vesting, percentage	50.00%
Options vested	50
2018 Stock Incentive Plan
Share-Based Compensation
Common stock reserved for issuance						4,000,000
2020 Stock Incentive Plan
Share-Based Compensation
Common stock reserved for issuance					3,000,000
2024 Stock Incentive Plan
Share-Based Compensation
Common stock reserved for issuance				3,000,000
Stock Option Plan
Share-Based Compensation
Stock option vesting period	2 years
Options granted under the Plans expire	10 years
Option to purchase granted	147,495		675,939
Stock Option Plan \| Minimum
Share-Based Compensation
Expected lives	3 years
Stock Option Plan \| Maximum
Share-Based Compensation
Expected lives	10 years
Incentive Stock Options
Share-Based Compensation
Options granted under the Plans expire	5 years
Stock Appreciation Rights (SARs)
Share-Based Compensation
Stock option vesting period			2 years
Option to purchase granted			67,500
Options unvested	391,140
Location, Statement of Income, Balance [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense
Share-Based Compensation
Share-based compensation expense	$ 0.8	$ 0.5