Components of Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands		12 Months Ended
		May. 31, 2015	May. 31, 2014	May. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of May 31, 2014		$ (3,581)
Other comprehensive loss before reclassifications		(66,363)
Reclassification adjustments to income	[1]	10,374
Income taxes		8,866	$ (528)	$ (2,178)
Balance as of May 31, 2015		(50,704)	(3,581)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of May 31, 2014		11,015
Other comprehensive loss before reclassifications		(31,732)
Balance as of May 31, 2015		(20,717)	11,015
Pension Liability Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of May 31, 2014		(11,265)
Other comprehensive loss before reclassifications		(5,979)
Reclassification adjustments to income	[1]	327
Income taxes		1,914
Balance as of May 31, 2015		(15,003)	(11,265)
Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance as of May 31, 2014		(3,331)
Other comprehensive loss before reclassifications		(28,652)
Reclassification adjustments to income	[1]	10,047
Income taxes		6,952
Balance as of May 31, 2015		$ (14,984)	$ (3,331)

[1] The statement of earnings classification of amounts reclassified to income for cash flow hedges is disclosed in "Note P - Derivative Instruments and Hedging Activities."