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Note 16 - Retirement Benefit Plans - Plan Assets and Benefit Obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Interest cost	$ (27.2)	$ (27.6)	$ (16.9)
Pension Plan [Member]
Fair value of plan assets	696.4	660.5
Return on plan assets	(32.9)	15.2
Employer contributions	2.4	2.2
Benefits paid	(19.5)	(17.9)
Settlements	(9.6)	(3.2)
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	(11.7)	39.6
Fair value of plan assets	625.1	696.4	660.5
Benefit obligation as of January 1	(611.1)	(565.6)
Interest cost	(27.2)	(27.6)
Settlements	9.6	3.2
Benefits paid	19.5	17.9
Actuarial gain/(loss)	42.1	(5.1)
Foreign currency translation	10.3	(33.9)
Benefit obligation as of December 31	(556.8)	(611.1)	$ (565.6)
Funded status as of year-end	68.3	85.3
Net retirement benefit asset recognized in the Consolidated Balance Sheets	$ 68.3	$ 85.3

X

- Definition

Amount of funded (unfunded) status of defined benefit plan before income tax, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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