Reconciliation of Our Tax Contingencies (Detail) - USD ($) $ in Millions	12 Months Ended
May 31, 2026	May 31, 2025	May 31, 2024
Income Tax Contingency [Line Items]
Beginning balance	$ 3.8	$ 2.7	$ 0.9
Increase/(decrease) related to prior periods	(0.1)	0.1	0.0
Increase related to current period	1.5	1.1	2.0
Lapses of applicable statute of limitations	(0.2)	(0.1)	(0.2)
Ending balance	$ 5.0	$ 3.8	$ 2.7

Unrecognized Tax Benefits Increase Decrease Resulting From Current Period Tax Positions.

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- Definition

Unrecognized Tax Benefits Increase Decrease Resulting From Prior Period Tax Positions

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 217
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-217

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Name Accounting Standards Codification
-Section 50
-Paragraph 15A
-Subparagraph (a)
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Name Accounting Standards Codification
-Section 45
-Paragraph 10B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482525/740-10-45-10B

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- Definition

Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15A
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-15A

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