Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Aug. 31, 2013		Aug. 31, 2012		Aug. 31, 2011
Reserve for doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Allowances and Reserves, Balance at Beginning of Year	$ 1.4		$ 1.8		$ 2.0
Valuation Allowances and Reserves, Charged to Cost and Expense	0.2		0.4		0.4
Valuation Allowances and Reserves, Charged to Other Accounts	0	[1]	0	[1]	0.1	[1]
Valuation Allowances and Reserves, Deductions	0.1		0.8		0.7
Valuation Allowances and Reserves, Balance at End of Year	1.5		1.4		1.8
Reserve for estimated warranty and recall costs
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Allowances and Reserves, Balance at Beginning of Year	4.0		4.2		3.6
Valuation Allowances and Reserves, Charged to Cost and Expense	6.7		5.6		5.1
Valuation Allowances and Reserves, Charged to Other Accounts	0	[1]	0	[1]	0.6	[1]
Valuation Allowances and Reserves, Deductions	4.8		5.8		5.1
Valuation Allowances and Reserves, Balance at End of Year	5.9		4.0		4.2
Reserve for estimated returns and allowances
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Allowances and Reserves, Balance at Beginning of Year	3.9		4.9		4.8
Valuation Allowances and Reserves, Charged to Cost and Expense	48.9		39.6		45.5
Valuation Allowances and Reserves, Charged to Other Accounts	0	[1]	0	[1]	0	[1]
Valuation Allowances and Reserves, Deductions	48.1		40.6		45.4
Valuation Allowances and Reserves, Balance at End of Year	4.7		3.9		4.9
Self-insurance reserve
Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation Allowances and Reserves, Balance at Beginning of Year	8.5	[2]	9.1	[2]	9.5	[2]
Valuation Allowances and Reserves, Charged to Cost and Expense	7.3	[2]	5.8	[2]	6.0	[2]
Valuation Allowances and Reserves, Charged to Other Accounts	0.4	[1],[2]	0.5	[1],[2]	0	[1],[2]
Valuation Allowances and Reserves, Deductions	7.0	[2]	6.9	[2]	6.4	[2]
Valuation Allowances and Reserves, Balance at End of Year	$ 9.2	[2]	$ 8.5	[2]	$ 9.1	[2]

[1] Includes recoveries and adjustments credited to the reserve.

[2] Includes reserves for workers’ compensation, auto, product, and general liability claims.