Stock-Based Compensation (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2023	Nov. 30, 2022	Nov. 30, 2023	Nov. 30, 2022
Stock-Based Compensation (Details) - Schedule of stock-based compensation [Line Items]
Stock-based compensation expense	$ 4.1	$ 4.2	$ 6.4	$ 5.9
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	0.3	0.3	0.4	0.6
Stock option expense
Stock-Based Compensation (Details) - Schedule of stock-based compensation [Line Items]
Stock-based compensation expense	$ 2.4	$ 2.4	$ 3.0	$ 3.0
Restricted stock unit expense
Stock-Based Compensation (Details) - Schedule of stock-based compensation [Line Items]
Stock-based compensation expense	1.4	1.3	2.9	2.3
Management stock purchase plan
Stock-Based Compensation (Details) - Schedule of stock-based compensation [Line Items]
Stock-based compensation expense	0.3	0.4	0.3	0.4
Employee stock purchase plan
Stock-Based Compensation (Details) - Schedule of stock-based compensation [Line Items]
Stock-based compensation expense	$ 0.0	$ 0.1	$ 0.2	$ 0.2