Summary of Significant Accounting Policies - Financial Instruments (Details) - USD ($) $ in Millions	May 31, 2025	May 31, 2024
Accounts Receivable
Accounts receivable, less allowances of $10.1 and $14.1, respectively	$ 354.8	$ 287.2
U.S. Government contracts
Accounts Receivable
Accounts receivable, less allowances of $10.1 and $14.1, respectively	40.0	43.8
U.S. Government contracts \| Trade receivables
Accounts Receivable
Trade receivables	26.6	34.4
U.S. Government contracts \| Unbilled receivables
Accounts Receivable
Unbilled receivables	13.4	9.4
All other customers
Accounts Receivable
Accounts receivable, less allowances of $10.1 and $14.1, respectively	314.8	243.4
All other customers \| Trade receivables
Accounts Receivable
Trade receivables	283.4	216.1
All other customers \| Unbilled receivables
Accounts Receivable
Unbilled receivables	$ 31.4	$ 27.3

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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- References

No definition available.

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

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- Definition

Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

+ References

No definition available.

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