Subsequent Event (Details) - Subsequent Event [Member]	3 Months Ended
Oct. 31, 2017 $ / shares
Subsequent Event [Line Items]
Dividends Payable, Date Declared	Aug. 17, 2017
Dividends Payable, Amount Per Share	$ 0.50
Dividends Payable, Date to be Paid	Oct. 10, 2017
Dividends Payable, Date of Record	Sep. 20, 2017

Date the declared dividend will be paid, in CCYY-MM-DD format.

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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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