Derivative Financial Instruments (Details 4) - USD ($) $ in Millions	Apr. 30, 2017	Apr. 30, 2016
Commodity contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gross contract notional amount	$ 704.9	$ 545.7
Foreign currency exchange contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gross contract notional amount	$ 195.4	$ 212.5

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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