Noncontrolling Interests - Reconciliation of Net Income Attributable to Non Controlling Interest (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2014	Feb. 28, 2013	Feb. 28, 2014	Feb. 28, 2013
Noncontrolling Interest [Abstract]
Net income attributable to noncontrolling interests, net of tax	$ 5,000	$ 4,352	$ 18,025	$ 17,027
Foreign currency translation attributable to nonredeemable noncontrolling interests	2,181	878	8,798	7,857
Foreign currency translation attributable to redeemable non-controlling interests			0	573
Comprehensive income attributable to noncontrolling interests, net of tax	$ 7,181	$ 5,230	$ 26,823	$ 25,457