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Summary Of Significant Accounting Policies [Line Items]

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Summary of Significant Accounting Policies (Details)	12 Months Ended
Summary of Significant Accounting Policies (Details)	Apr. 30, 2019 USD ($) plan	Apr. 30, 2018 USD ($)	Apr. 30, 2017 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Advertising costs	$ 38,900,000	$ 40,100,000	$ 41,000,000
Impairment of long-lived assets	0	0	0
Impairment of goodwill	0	0	0
Impairment of intangible assets	$ 0	0	0
Number of defined benefit pension plans \| plan	2
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, useful life	3 years
Minimum [Member] \| Accounting Standards Update 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Right-of-use asset	$ 95,000,000
Operating lease liability	$ 95,000,000
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Intangible assets, useful life	6 years
Maximum [Member] \| Accounting Standards Update 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Right-of-use asset	$ 115,000,000
Operating lease liability	$ 115,000,000
Buildings And Improvements [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	15 years
Buildings And Improvements [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	30 years
Machinery And Equipment [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	3 years
Machinery And Equipment [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	12 years
Promotional Display [Member]
Summary Of Significant Accounting Policies [Line Items]
Amortization	$ 6,400,000	$ 4,500,000	$ 3,400,000
Promotional Display [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	24 months
Promotional Display [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment useful lives	60 months