Pensions and Other Postretirement Benefits (Details 6) - Defined Benefit Pension Plans [Member] - USD ($) $ in Millions	Apr. 30, 2020	Apr. 30, 2019
Additional information related to the Company's defined benefit pension plans
Accumulated benefit obligation for all pension plans	$ 642.8	$ 605.6
Plans with an accumulated benefit obligation in excess of plan assets:
Accumulated benefit obligation	563.4	521.5
Fair value of plan assets	380.6	388.2
Plans with a projected benefit obligation in excess of plan assets:
Projected benefit obligation	572.9	531.4
Fair value of plan assets	$ 380.6	$ 388.2

Additional information related to company's defined benefit pension plans.

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

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