Pensions and Other Postretirement Benefits (Details 4) - USD ($) $ in Millions	Apr. 30, 2024	Apr. 30, 2023
Defined Benefit Pension Plans
Accumulated other comprehensive income (loss)
Net actuarial gain (loss)	$ (96.8)	$ (92.5)
Prior service credit (cost)	(0.4)	(0.5)
Total recognized in accumulated other comprehensive income (loss)	(97.2)	(93.0)
Other Postretirement Benefits
Accumulated other comprehensive income (loss)
Net actuarial gain (loss)	25.5	21.7
Prior service credit (cost)	1.9	2.5
Total recognized in accumulated other comprehensive income (loss)	$ 27.4	$ 24.2

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-14A

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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