Condensed Consolidated Statements of Changes in Equity - 9 months ended Feb. 28, 2017 - USD ($) $ in Millions	Common Stock	Capital Surplus	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Loss	Total
Balance at May. 31, 2016	$ 44.9	$ 451.3	$ 681.6	$ (267.6)	$ (44.4)	$ 865.8
Increase (Decrease) in Stockholders' Equity
Net income			35.3			35.3
Cash dividends			(7.7)			(7.7)
Stock option activity		2.0		5.9		7.9
Restricted stock activity	0.3	4.0		(1.3)		3.0
Repurchase of shares				(16.6)		(16.6)
Other comprehensive loss, net of tax					(2.0)	(2.0)
Balance at Feb. 28, 2017	$ 45.2	$ 457.3	$ 709.2	$ (279.6)	$ (46.4)	$ 885.7