Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Millions	Common Stock	Capital Surplus	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Loss.	Total
Balance at May. 31, 2021	$ 45.3	$ 479.8	$ 741.7	$ (274.1)	$ (18.3)	$ 974.4
Increase (Decrease) in Stockholders' Equity
Net income			11.5			11.5
Stock option activity		1.1		0.2		1.3
Restricted stock activity		(1.0)		2.3		1.3
Other comprehensive loss, net of tax					(0.3)	(0.3)
Balance at Aug. 31, 2021	45.3	479.9	753.2	(271.6)	(18.6)	988.2
Balance at May. 31, 2022	45.3	477.5	820.4	(289.1)	(19.6)	1,034.5
Increase (Decrease) in Stockholders' Equity
Net income			22.7			22.7
Stock option activity		1.0		1.5		2.5
Restricted stock activity		(1.7)		3.5		1.8
Repurchase of shares				(21.9)		(21.9)
Other comprehensive loss, net of tax					(3.1)	(3.1)
Balance at Aug. 31, 2022	$ 45.3	$ 476.8	$ 843.1	$ (306.0)	$ (22.7)	$ 1,036.5