Amount of discretionary contributions made by an employer to a defined benefit plan.

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Amount of benefits for defined benefit plan expected to be paid in periods following the current period.

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- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

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Amount of cost for defined contribution plan.

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Amount of liability for retirement benefits, classified as other.

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Retirement Plans, Expected Employer Contributions and Benefit Payments and Other Retirement Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions to the defined benefit pension plans	$ 16,900
Discretionary contribution	10,000
Expected future benefit payments [Abstract]
2021	26,314
2022	25,948
2023	26,598
2024	27,404
2025	28,802
2026-2030	148,862
Total	283,928
Defined Contribution Savings Plans [Abstract]
Expense recorded	19,000	$ 13,100	$ 14,400
U.S. [Member]
Expected future benefit payments [Abstract]
2021	16,581
2022	15,205
2023	15,533
2024	15,713
2025	15,363
2026-2030	77,026
Total	155,421
Other postretirement benefits [Abstract]
Annual (credits) expenses for benefit plans	(542)	113	647
Non-U.S. [Member]
Expected future benefit payments [Abstract]
2021	9,733
2022	10,743
2023	11,065
2024	11,691
2025	13,439
2026-2030	71,836
Total	128,507
Other postretirement benefits [Abstract]
Annual (credits) expenses for benefit plans	(7,256)	(7,893)	(7,641)
Non-U.S. [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected employer contributions to the defined benefit pension plans	11,800
Postretirement Life Insurance and Health Care Benefits [Member]
Other postretirement benefits [Abstract]
Accumulated post-retirement benefit obligation	1,400	1,600
Annual (credits) expenses for benefit plans	$ (100)	$ (100)	$ (100)