Guarantor and Non-Guarantor Financial Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jul. 31, 2013	Jul. 31, 2012
Condensed Statements of Consolidated Income and Comprehensive Income
Net sales	$ 1,350.9	$ 1,369.7
Cost of products sold	858.0	899.9
Gross Profit	492.9	469.8
Selling, distribution, and administrative expenses, restructuring, merger and integration, and other special project costs	256.0	256.1
Amortization	24.5	24.2
Other operating income - net	(0.9)	(1.0)
Operating Income	213.3	190.5
Interest (expense) income - net	(23.8)	(23.6)
Other income (expense) - net	0	0.4
Equity in net earnings of subsidiaries	0	0
Income Before Income Taxes	189.5	167.3
Income taxes	62.9	56.4
Net Income	126.6	110.9
Other comprehensive (loss) income, net of tax	(2.7)	(0.4)
Comprehensive Income	123.9	110.5
[ParentCompanyMember]
Condensed Statements of Consolidated Income and Comprehensive Income
Net sales	736.0	702.5
Cost of products sold	600.4	593.0
Gross Profit	135.6	109.5
Selling, distribution, and administrative expenses, restructuring, merger and integration, and other special project costs	48.6	56.9
Amortization	1.1	2.9
Other operating income - net	(1.5)	(0.7)
Operating Income	87.4	50.4
Interest (expense) income - net	(24.0)	(23.8)
Other income (expense) - net	0	4.5
Equity in net earnings of subsidiaries	82.6	89.3
Income Before Income Taxes	146.0	120.4
Income taxes	19.4	9.5
Net Income	126.6	110.9
Other comprehensive (loss) income, net of tax	(2.7)	(0.4)
Comprehensive Income	123.9	110.5
[SubsidiariesMember]
Condensed Statements of Consolidated Income and Comprehensive Income
Net sales	303.4	318.2
Cost of products sold	277.4	290.8
Gross Profit	26.0	27.4
Selling, distribution, and administrative expenses, restructuring, merger and integration, and other special project costs	10.9	11.9
Amortization	0	0
Other operating income - net	(0.2)	(0.5)
Operating Income	15.3	16.0
Interest (expense) income - net	0.3	0.3
Other income (expense) - net	0.1	0.5
Equity in net earnings of subsidiaries	32.9	33.2
Income Before Income Taxes	48.6	50.0
Income taxes	0.1	0.1
Net Income	48.5	49.9
Other comprehensive (loss) income, net of tax	1.9	2.3
Comprehensive Income	50.4	52.2
[NonGuarantorSubsidiariesMember]
Condensed Statements of Consolidated Income and Comprehensive Income
Net sales	1,593.4	1,309.2
Cost of products sold	1,257.9	973.6
Gross Profit	335.5	335.6
Selling, distribution, and administrative expenses, restructuring, merger and integration, and other special project costs	196.5	187.3
Amortization	23.4	21.3
Other operating income - net	0.8	0.2
Operating Income	114.8	126.8
Interest (expense) income - net	(0.1)	(0.1)
Other income (expense) - net	(0.1)	(4.6)
Equity in net earnings of subsidiaries	15.4	16.5
Income Before Income Taxes	130.0	138.6
Income taxes	43.4	46.8
Net Income	86.6	91.8
Other comprehensive (loss) income, net of tax	(3.9)	(2.5)
Comprehensive Income	82.7	89.3
[ConsolidationEliminationsMember]
Condensed Statements of Consolidated Income and Comprehensive Income
Net sales	(1,281.9)	(960.2)
Cost of products sold	(1,277.7)	(957.5)
Gross Profit	(4.2)	(2.7)
Selling, distribution, and administrative expenses, restructuring, merger and integration, and other special project costs	0	0
Amortization	0	0
Other operating income - net	0	0
Operating Income	(4.2)	(2.7)
Interest (expense) income - net	0	0
Other income (expense) - net	0	0
Equity in net earnings of subsidiaries	(130.9)	(139.0)
Income Before Income Taxes	(135.1)	(141.7)
Income taxes	0	0
Net Income	(135.1)	(141.7)
Other comprehensive (loss) income, net of tax	2.0	0.2
Comprehensive Income	$ (133.1)	$ (141.5)