Goodwill and Other Intangibles - Schedule of activity in goodwill (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Aug. 31, 2022	Aug. 31, 2021	May 31, 2022	May 31, 2021
Goodwill [Roll Forward]
Gross goodwill			$ 164.9	$ 165.9
Accumulated impairment			(39.6)	$ (39.6)
Beginning balance	$ 125.3	$ 126.3	126.3
Foreign currency translation	(0.6)	(0.4)	(1.0)
Ending balance	$ 124.7	$ 125.9	$ 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 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

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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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