Summary of Changes in Total Equity, Shareholders' Equity Attributable to Controlling Interest, and Equity Attributable to Noncontrolling Interests (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 29, 2016	Feb. 28, 2015	Feb. 29, 2016	Feb. 28, 2015
Beginning Balance			$ 840,049
Net earnings	$ 33,872	$ (23,245)	93,925	$ 57,030
Other comprehensive income	13,986	$ (25,112)	4,694	$ (42,894)
Common shares issued, net of withholding tax			5,811
Common shares in NQ plans			881
Stock-based compensation			13,466
Purchases and retirement of common shares			(99,848)
Cash dividends declared			(36,058)
Payments to noncontrolling interest			(9,106)
Ending Balance	813,814		813,814
Additional Paid-in Capital
Beginning Balance			289,078
Common shares issued, net of withholding tax			5,811
Common shares in NQ plans			881
Stock-based compensation			13,466
Purchases and retirement of common shares			(16,296)
Ending Balance	292,940		292,940
Cumulative Other Comprehensive Income (Loss), Net of Tax
Beginning Balance			(50,704)
Other comprehensive income			2,185
Ending Balance	(48,519)		(48,519)
Retained Earnings
Beginning Balance			510,738
Net earnings			84,227
Purchases and retirement of common shares			(83,552)
Cash dividends declared			(36,058)
Ending Balance	475,355		475,355
Parent
Beginning Balance			749,112
Net earnings			84,227
Other comprehensive income			2,185
Common shares issued, net of withholding tax			5,811
Common shares in NQ plans			881
Stock-based compensation			13,466
Purchases and retirement of common shares			(99,848)
Cash dividends declared			(36,058)
Ending Balance	719,776		719,776
Noncontrolling Interest
Beginning Balance			90,937
Net earnings			9,698
Other comprehensive income			2,509
Payments to noncontrolling interest			(9,106)
Ending Balance	$ 94,038		$ 94,038