Percentage of fair market value in the case of persons holding 10% or more of the voting stock of the company.

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Amount of intrinsic value of equity-based compensation awards not vested.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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

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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.

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

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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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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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Number of options vested.

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Share-based compensation (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
Share-based compensation (Details) - USD ($) $ in Millions	Jan. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Jun. 11, 2020	Jun. 07, 2018	Sep. 17, 2014
Share-based compensation
Common stock reserved for issuance		4,315,653
Stock option vesting period				1 year
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		$ 20.1		$ 26.9
Intrinsic value of options unvested		0.0		$ 0.8
Intrinsic value of options exercised		$ 0.1	$ 0.1
Stock Option Plan
Share-based compensation
Stock option vesting period		2 years
Stock option vesting, percentage				50.00%
Option to purchase granted		42,791		584,826
Options vested				337,727
Minimum \| Stock Option Plan
Share-based compensation
Contractual term		3 years
Maximum \| Stock Option Plan
Share-based compensation
Contractual term		10 years
Tranche one
Share-based compensation
Stock option vesting, percentage		50.00%
Tranche two
Share-based compensation
Stock option vesting period		1 year
Stock option vesting, percentage		50.00%
2014 Stock Incentive Plan
Share-based compensation
Common stock reserved for issuance							3,000,000
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
Stock Option Plan
Share-based compensation
Options granted		42,791		602,526
Share-based awards at the granted
Share-based compensation
Options granted		42,791	484,701
Stock Appreciation Rights (SARs)
Share-based compensation
Stock option vesting period	6 months
Option to purchase granted	17,700
Selling, general and administrative expenses
Share-based compensation
Share based compensation expense		$ 0.3	$ 1.0