Income Taxes (Details 1) $ in Millions	12 Months Ended
Apr. 30, 2018 USD ($)
Income Tax Disclosure [Abstract]
Net impact on U.S. deferred tax assets and liabilities	$ (791.9)
Transition tax	26.1
Net impact of adjustments	$ (765.8)

Amount of income tax expense (benefit) attributable to an adjustment of a deferred tax liability or asset for the Tax Cuts and Jobs Act of 2017.

No definition available.

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Namespace Prefix:	sjm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration