Equity - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	May 31, 2016	May 31, 2015	May 31, 2014	Jun. 25, 2014	Jun. 29, 2011
Class of Stock [Line Items]
Common Stock remaining shares authorized for repurchase		0
Purchases of common shares (in shares)		1,722,332
Repurchase of common shares	$ 99,847	$ 127,360	$ 128,218
Purchases and retirement of common shares (in shares)	3,500,000	4,176,187
Deferred compensation obligation credited to common share option	$ 960	$ 14,560
Stock repurchase on June 25, 2014
Class of Stock [Line Items]
Common Stock remaining shares authorized for repurchase	4,046,145
Purchases of common shares (in shares)	3,500,000	2,453,855
Maximum
Class of Stock [Line Items]
Common Stock shares authorized for repurchase					10,000,000
Maximum | Stock repurchase on June 25, 2014
Class of Stock [Line Items]
Common Stock shares authorized for repurchase				10,000,000