Computation of Basic and Diluted Earnings (Loss) Per Share Attributable to Controlling Interest (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 29, 2016	Feb. 28, 2015	Feb. 29, 2016	Feb. 28, 2015
Numerator (basic & diluted):
Net earnings (loss) attributable to controlling interest - income (loss) available to common shareholders	$ 29,576	$ (25,710)	$ 84,227	$ 47,920
Denominator:
Denominator for basic earnings (loss) per share attributable to controlling interest - weighted average common shares	61,747	66,359	62,810	67,013
Effect of dilutive securities	1,980		1,773	2,288
Denominator for diluted earnings (loss) per share attributable to controlling interest - adjusted weighted average common shares	63,727	66,359	64,583	69,301
Basic earnings (loss) per share attributable to controlling interest	$ 0.48	$ (0.39)	$ 1.34	$ 0.72
Diluted earnings (loss) per share attributable to controlling interest	$ 0.46	$ (0.39)	$ 1.30	$ 0.69