Targeted annual dividend per share amount.

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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Stockholders' Equity (Details) (USD $)	3 Months Ended	6 Months Ended
Stockholders' Equity (Details) (USD $)	Jan. 31, 2015	Jan. 31, 2015	Jan. 31, 2014	Mar. 10, 2015	Oct. 09, 2014	Dec. 10, 2014	Mar. 11, 2015
Stock Repurchase Program
Treasury Stock, Shares, Acquired	0us-gaap_TreasuryStockSharesAcquired	0us-gaap_TreasuryStockSharesAcquired	935,992us-gaap_TreasuryStockSharesAcquired
Average price per share of shares repurchased on the open market			$ 31.10
Aggregate cost including transaction costs			$ 29,107,000
Maximum amount authorized by the Board of Directors for repurchases of the Company's common stock	100,000,000	100,000,000
Stock repurchase program, remaining authorized repurchase amount	13,650,000	13,650,000
Dividends
Targeted annual dividend per share	$ 1.20	$ 1.20
Subsequent
Stock Repurchase Program
Stock repurchase program, remaining authorized repurchase amount				$ 13,650,000
Quarterly Dividend - First
Dividends
Quarterly dividend payment amount per share					$ 0.30
Quarterly Dividend - Second
Dividends
Quarterly dividend payment amount per share						$ 0.30
Dividend Declared - Third \| Subsequent
Dividends
Quarterly dividend payment amount per share							$ 0.30