Derivative Instruments and Hedging Activities - Additional Information (Detail) - USD ($)	12 Months Ended
	May 31, 2017	May 31, 2016
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate impact to fair value of derivative assets and liabilities as a result of recognition on a net basis	$ 100,000	$ (300,000)
Losses in accumulated other comprehensive income expected to be reclassified into net earnings	6,166,000
Losses in accumulated other comprehensive income expected to be reclassified into net earnings, tax	$ 3,770,000