Employee Benefit Plans - Schedule of accumulated benefit obligation in excess of plan assets (Details) - U.K. - Pension Plans - USD ($) $ in Millions	May 31, 2022	May 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	$ 31.9	$ 47.0
Accumulated benefit obligations	31.6	46.5
Fair value of plan assets	$ 30.4	$ 40.8

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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