v3.26.1
Pensions and Other Postretirement Benefits (Details) - USD ($)
$ in Millions
 12 Months Ended
Apr. 30, 2026
Apr. 30, 2025
Apr. 30, 2024
Components of net periodic benefit cost:      
Settlement loss (gain) $ 34.4 $ 0.0 $ 3.2
Defined Benefit Pension Plans      
Components of net periodic benefit cost:      
Service cost 0.7 0.7 0.9
Interest cost 14.9 17.7 18.5
Expected return on plan assets (13.2) (12.3) (16.1)
Amortization of prior service cost (credit) 0.2 0.1 0.1
Amortization of net actuarial loss (gain) 3.9 4.3 3.5
Curtailment loss (gain) 0.0 0.0 (1.2)
Settlement loss (gain) 34.4 0.0 3.2
Net periodic benefit cost 40.9 10.5 8.9
Other Postretirement Benefits      
Components of net periodic benefit cost:      
Service cost 0.7 0.6 0.8
Interest cost 2.4 2.7 2.6
Expected return on plan assets 0.0 0.0 0.0
Amortization of prior service cost (credit) (0.6) (0.6) (0.6)
Amortization of net actuarial loss (gain) (1.9) (2.0) (1.5)
Curtailment loss (gain) 0.0 0.0 0.0
Settlement loss (gain) 0.0 0.0 0.0
Net periodic benefit cost $ 0.6 $ 0.7 $ 1.3