Income Taxes (Details 1) (USD $) In Millions, unless otherwise specified	12 Months Ended
Apr. 30, 2011	Apr. 30, 2010	Apr. 30, 2009
Reconciles our effective tax rate to the federal statutory tax rate in the United States
U.S. federal statutory rate	35.00%	35.00%	35.00%
State taxes, net of U.S. federal tax benefit	1.10%	1.80%	1.80%
Income taxed at other than U.S. federal statutory rate	(0.40%)	(1.00%)	(1.30%)
Tax benefit from U.S. manufacturing	(2.20%)	(1.70%)	(1.70%)
Capital loss benefit	(2.70%)		(1.20%)
Nondeductible goodwill on Fetzer sale	2.10%
Other, net	(1.90%)		(1.50%)
Effective rate	31.00%	34.10%	31.10%
Reconciliation of beginning and ending unrecognized tax benefits
Unrecognized tax benefits at beginning of year	$ 35	$ 26	$ 35
Additions for tax positions provided in prior periods	1		1
Additions for tax positions provided in current period	14	13	4
Decreases for tax positions provided in prior years	(4)
Settlements of tax positions in the current period	(5)	(3)	(2)
Lapse of statutes of limitations	(1)	(1)	(12)
Unrecognized tax benefits at end of year	$ 40	$ 35	$ 26

Effective Income Tax Rate Reconciliation Deductions Capital Loss Benefit.

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Effective income tax rate reconciliation nondeductible goodwill on sale.

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to the deduction for qualified production activities received under enacted tax laws.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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