Proforma Results of Operations (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Nov. 30, 2012	Nov. 30, 2011
Business Acquisition, Pro Forma Information [Line Items]
Net sales, As reported	$ 377,248	$ 392,799
Net sales, Pro forma	377,248	415,787
Net earnings, As reported	36,343	37,174
Net earnings, Pro forma	$ 36,502	$ 40,097
Basic earnings per share, As reported	$ 0.50	$ 0.54
Basic earnings per share, Pro forma	$ 0.50	$ 0.59
Diluted earnings per share, As reported	$ 0.49	$ 0.50
Diluted earnings per share, Pro forma	$ 0.49	$ 0.54

The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect per basic share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References+ Details

The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References+ Details

- Definition

Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

+ References

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+ Details

- Definition

The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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+ Details

- Definition

The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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