Pensions and Other Postretirement Benefits (Details 4) - USD ($) $ in Millions	Apr. 30, 2025	Apr. 30, 2024
Defined Benefit Pension Plans
Accumulated other comprehensive income (loss)
Net actuarial gain (loss)	$ (91.2)	$ (96.8)
Prior service credit (cost)	(0.6)	(0.4)
Total recognized in accumulated other comprehensive income (loss)	(91.8)	(97.2)
Other Postretirement Benefits
Accumulated other comprehensive income (loss)
Net actuarial gain (loss)	21.2	25.5
Prior service credit (cost)	1.3	1.9
Total recognized in accumulated other comprehensive income (loss)	$ 22.5	$ 27.4

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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