Benefit Plans - Obligations and Funded Status (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Change in benefit obligations
Service cost	$ 1.4	$ 1.7	$ 1.7
Interest cost	3.8	3.9	4.1
Net actuarial loss (gain)	2.3	(2.9)	7.1
Change in plan assets
Fair value of plan assets beginning of year	27.4
Fair value of plan assets end of year	31.8	27.4
Pension plans
Change in benefit obligations
Benefit obligation beginning of year	83.3	97.5
Service cost	1.4	1.7
Interest cost	3.8	3.9
Net actuarial loss (gain)	3.0	(2.7)
Translation (gain) loss	1.6	(1.1)
Benefits paid	(7.7)	(7.2)
Benefit obligation end of year	85.4	83.3	97.5
Change in plan assets
Fair value of plan assets beginning of year	27.4	30.5
Actual return on plan assets	1.1	0.6
Company contributions	9.8	11.2
Defined Benefit Plan, Plan Assets, Payment for Settlement	0.0	(6.8)
Translation gain (loss)	1.2	(0.9)
Benefits paid	(7.7)	(7.2)
Fair value of plan assets end of year	31.8	27.4	30.5
Funded status
Plan assets less than benefit obligation	(53.6)	(55.9)
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment	0.0	(2.0)
Lump-sum payments	0.0	(6.8)
Other post-retirement plans
Change in benefit obligations
Benefit obligation beginning of year	6.6	7.6
Service cost	0.0	0.0
Interest cost	0.3	0.4
Net actuarial loss (gain)	0.2	(0.6)
Translation (gain) loss	0.0	0.0
Benefits paid	(0.8)	(0.8)
Benefit obligation end of year	6.3	6.6	7.6
Change in plan assets
Fair value of plan assets beginning of year	0.0	0.0
Actual return on plan assets	0.0	0.0
Company contributions	0.8	0.8
Defined Benefit Plan, Plan Assets, Payment for Settlement	0.0	0.0
Translation gain (loss)	0.0	0.0
Benefits paid	(0.8)	(0.8)
Fair value of plan assets end of year	0.0	0.0	$ 0.0
Funded status
Plan assets less than benefit obligation	(6.3)	(6.6)
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment	0.0	0.0
Lump-sum payments	$ 0.0	$ 0.0