Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 56,958	$ 48,074
Other comprehensive income (loss):
Foreign currency translation	(3,695)	15,872
Pension liability adjustment, net of tax	(97)	(6)
Cash flow hedges, net of tax	(1,970)	1,887
Other comprehensive income (loss)	(5,762)	17,753
Comprehensive income	51,196	65,827
Comprehensive income attributable to noncontrolling interests	1,999	2,979
Comprehensive income attributable to controlling interest	$ 49,197	$ 62,848

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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