Earnings Per Share (Schedule Of Reconciliations Between Basic And Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Feb. 29, 2012	Feb. 28, 2011	Feb. 29, 2012	Feb. 28, 2011
Earnings Per Share [Abstract]
Net earnings from continuing operations	$ 32,175	$ 22,142	$ 69,349	$ 48,803
Plus: 2% Convertible Notes financings costs, net of taxes	383	383	893	839
Interest rate on Convertible Notes	2.00%	2.00%	2.00%	2.00%
Net earnings for diluted earnings per share	$ 32,558	$ 22,525	$ 70,242	$ 49,642
Weighted average common shares outstanding for basic earnings per share	68,064	68,270	68,242	68,135
Net effect of dilutive securities - equity based compensation plans	1,084	1,257	925	1,093
Net effect of 2% Convertible Notes based on the if-converted method	5,957	5,968	5,957	5,958
Weighted average common and equivalent shares outstanding for diluted earnings per share	75,105	75,495	75,124	75,186
Basic Earnings Per Share:	$ 0.47	$ 0.32	$ 1.02	$ 0.72
Diluted Earnings Per Share:	$ 0.43	$ 0.30	$ 0.94	$ 0.66
Anti-dilutive securities-equity based compensation plans (excluded from earnings per share calculation)	2,175	1,825	3,016	2,511

Convertible notes financing costs, net of taxes.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Interest rate stated in the contractual debt agreement.

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This element represents the income or loss from continuing operations attributable to the parent which may also be 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, if any.

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