Computation of Basic and Diluted Earnings Per Share Attributable to Controlling Interest (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Aug. 31, 2017	Aug. 31, 2016
Numerator (basic & diluted):
Net earnings attributable to controlling interest -income available to common shareholders	$ 45,534	$ 65,567
Denominator:
Denominator for basic earnings per share attributable to controlling interest-weighted average common shares	62,444	61,885
Effect of dilutive securities	2,146	2,452
Denominator for diluted earnings per share attributable to controlling interest-adjusted weighted average common shares	64,590	64,337
Basic earnings per share attributable to controlling interest	$ 0.73	$ 1.06
Diluted earnings per share attributable to controlling interest	$ 0.70	$ 1.02