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Capital Stock and Share Repurchase Capital Stock and Share Repurchase Additional Information (Details) (USD $)
In Millions, except Share data, unless otherwise specified |
3 Months Ended | ||||
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Nov. 30, 2014
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Oct. 01, 2014
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Aug. 31, 2014
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Mar. 19, 2014
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Sep. 28, 2011
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| Equity [Abstract] | |||||
| Stock Repurchase Program, Number of Shares Authorized to be Repurchased | 7,000,000us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased | 7,000,000us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased | 7,000,000us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased | ||
| Stock Repurchase Program, Number of Shares Authorized to be Repurchased, Cumulative | 21,000,000atu_StockRepurchaseProgramNumberofSharesAuthorizedtobeRepurchasedCumulative | ||||
| Treasury Stock, Shares | 15,511,517us-gaap_TreasuryStockShares | 12,195,359us-gaap_TreasuryStockShares | |||
| Treasury Stock, Shares, Acquired | 3,316,158us-gaap_TreasuryStockSharesAcquired | ||||
| Treasury Stock, Value, Acquired, Cost Method | $ 104.4us-gaap_TreasuryStockValueAcquiredCostMethod | ||||
| Treasury Stock Acquired, Average Cost Per Share | $ 31.46us-gaap_TreasuryStockAcquiredAverageCostPerShare |
| X | ||||||||||
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- Definition
Stock Repurchase Program, Number of Shares Authorized to be Repurchased, Cumulative No definition available.
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- Details
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- Definition
The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. No definition available.
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- Definition
Total cost of shares repurchased divided by the total number of shares repurchased. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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