Schedule of Summary of Derivative Hedges (Detail) $ in Thousands	9 Months Ended
	Feb. 28, 2017 USD ($)
Commodity Contracts | Derivatives Not Designated As Hedging Instruments
Derivative [Line Items]
Notional Amount	$ 22,971
Commodity Contracts | Derivatives Not Designated As Hedging Instruments | Minimum
Derivative [Line Items]
Maturity Date	2017-03
Commodity Contracts | Derivatives Not Designated As Hedging Instruments | Maximum
Derivative [Line Items]
Maturity Date	2018-12
Foreign Currency Contracts | Derivatives Not Designated As Hedging Instruments
Derivative [Line Items]
Notional Amount	$ 15,450
Foreign Currency Contracts | Derivatives Not Designated As Hedging Instruments | Minimum
Derivative [Line Items]
Maturity Date	2017-03
Foreign Currency Contracts | Derivatives Not Designated As Hedging Instruments | Maximum
Derivative [Line Items]
Maturity Date	2017-08
Cash Flow Hedges | Commodity Contracts
Derivative [Line Items]
Notional Amount	$ 40,570
Cash Flow Hedges | Commodity Contracts | Minimum
Derivative [Line Items]
Maturity Date	2017-03
Cash Flow Hedges | Commodity Contracts | Maximum
Derivative [Line Items]
Maturity Date	2018-12
Cash Flow Hedges | Interest Rate Contracts
Derivative [Line Items]
Notional Amount	$ 16,183
Maturity Date	2019-09