Comprehensive Income (Allocation Of Total Comprehensive Income Between Controlling And Noncontrolling Interests) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Nov. 30, 2011	Nov. 30, 2010	Nov. 30, 2011	Nov. 30, 2010
Comprehensive Income [Abstract]
Net earnings, Controlling Interest	$ 11,985	$ 14,469	$ 37,637	$ 36,823
Net earnings, Noncontrolling Interest	2,216	2,414	4,904	4,313
Net earnings	14,201	16,883	42,541	41,136
Foreign currency translation, Controlling Interest	(9,554)	2,901	(9,032)	5,452
Foreign currency translation, Noncontrolling Interest	(1,520)		(2,341)
Foreign currency translation	(11,074)	2,901	(11,373)	5,452
Cash flow hedges, Controlling Interest	1,155	274	(880)	(1,777)
Cash flow hedges, Noncontrolling Interest
Cash flow hedges	1,155	274	(880)	(1,777)
Pension liability adjustment, Controlling Interest	49		49	12
Pension liability adjustment, Noncontrolling Interest
Pension liability adjustment	49		49	12
Comprehensive income, Controlling Interest	3,635	17,644	27,774	40,510
Comprehensive income, Noncontrolling Interest	696	2,414	2,563	4,313
Total comprehensive income	$ 4,331	$ 20,058	$ 30,337	$ 44,823