Goodwill and Other Intangibles - Schedule of activity in goodwill (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2023	May 31, 2022	May 31, 2021
Goodwill [Roll Forward]
Gross beginning balance	$ 164.9	$ 165.9
Goodwill, Impaired, Accumulated Impairment Loss	(39.6)	(39.6)	$ (39.6)
Beginning balance	125.3	126.3
Additions	7.6	0.0
Foreign currency translation	(0.2)	(1.0)
Gross ending balance	172.3	164.9
Ending balance	$ 132.7	$ 125.3

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.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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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.

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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.

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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.

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- Definition

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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