Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended	3 Months Ended
Feb. 28, 2014 Light_Fixture	Feb. 28, 2014 Selling, Distribution, and Administrative Expenses
Loss Contingencies [Line Items]
Number of light fixtures	1,700,000
Accrued liability for circuit board failures	$ 2.4
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Balance, beginning of period	5.9
Adjustments to the reserve	3.9
Payments made during the period	(1.4)
Balance, end of period	8.4
Estimate of loss		8.1
Payment received related to loss under insurance policy		$ 5.0

Product Liability Contingency, Number of Light Fixtures

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The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

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Undiscounted amount of the accrual for damages arising from third-party use of the entity's product or process.

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-Name Accounting Standards Codification

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

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Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard and extended product warranties (including adjustments for changes in estimates).

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