Derivative Instruments and Hedging Activities - Schedule of Derivatives Designated as Cash Flow Hedging Instruments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2019	Nov. 30, 2018
Derivative [Line Items]
Gain (Loss) Recognized in OCI	$ (316)	$ (4,499)	$ (5,975)	$ (4,530)
Gain (Loss) Reclassified from AOCI into Income	(4,332)	1,567	(6,666)	4,063
Commodity Contracts
Derivative [Line Items]
Gain (Loss) Recognized in OCI	10	(4,499)	(5,649)	(4,530)
Commodity Contracts | Cost of Sales
Derivative [Line Items]
Gain (Loss) Reclassified from AOCI into Income	(4,228)	1,565	(6,520)	4,108
Interest Rate Contract
Derivative [Line Items]
Gain (Loss) Recognized in OCI	(326)		(326)
Interest Rate Contract | Interest Expense
Derivative [Line Items]
Gain (Loss) Reclassified from AOCI into Income	(7)	(34)	(127)	(81)
Foreign Currency Exchange Contracts | Miscellaneous Income Expense
Derivative [Line Items]
Gain (Loss) Reclassified from AOCI into Income	$ (97)	$ 36	$ (19)	$ 36