Summary of Significant Accounting Policies - Revenue Recognition and Cumulative Catch-up Adjustments (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2023	May 31, 2022	May 31, 2021
Summary of Significant Accounting Policies
Favorable cumulative catch-up adjustments	$ 12.6	$ 15.0	$ 16.1
Unfavorable cumulative catch-up adjustments	(4.3)	(5.0)	(4.1)
Net cumulative catch-up adjustments	$ 8.3	$ 10.0	$ 12.0

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in estimates and assumptions used in calculating the cost-to-cost method.

No definition available.

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- References

No definition available.

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- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130551-203045

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- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

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