Income Taxes (Details 2) - USD ($) $ in Millions	12 Months Ended
Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2015
(Percent of Pretax Income)
Statutory federal income tax rate	35.00%	35.00%	35.00%
State and local income taxes	2.10%	2.50%	2.40%
Domestic manufacturing deduction	(3.70%)	(3.50%)	(2.90%)
Deferred tax benefit from integration	0.00%	(5.20%)	0.00%
Other items – net	(0.80%)	0.80%	(0.40%)
Effective income tax rate	32.60%	29.60%	34.10%
Income taxes paid	$ 367.2	$ 290.5	$ 199.3

Effective Income Tax Rate Reconciliation, Deferred Tax Benefit From Integration

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Percent of pretax income.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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