Goodwill and Other Intangibles - Schedule of activity in goodwill (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2022	May 31, 2021
Goodwill [Roll Forward]
Gross beginning balance	$ 165.9	$ 164.5
Accumulated impairment	(39.6)	(39.6)
Beginning balance	126.3	124.9
Foreign currency translation	$ (1.0)	1.4
Gross ending balance		$ 165.9

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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