Employee Benefit Plans - Schedule of expected future benefit payments (Details) $ in Millions	May 31, 2022 USD ($)
U.K. \| Pension Plans
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2023	$ 0.9
2024	1.3
2025	1.5
2026	1.5
2027	1.5
2028 - 2032	7.7
U.S. \| Other Postretirement Benefits
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2023	1.2
2024	1.1
2025	1.0
2026	0.9
2027	0.9
2028 - 2032	3.5
Medicare subsidy receipts
2023	0.1
2024	0.0
2025	0.0
2026	0.0
2027	0.0
2028 - 2032	$ 0.1

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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 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 prescription drug subsidy receipt expected after fifth fiscal year following current fiscal year.

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