Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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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.

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Subsequent Event - Additional Information (Detail) - $ / shares			3 Months Ended
	Aug. 22, 2018	May 16, 2018	Jul. 31, 2018	Jul. 31, 2017
Subsequent Event [Line Items]
Cash dividends declared per common share		$ 0.11	$ 0.11	$ 0.11
Cash dividend payable date			Aug. 31, 2018
Cash dividends declared, record date			Aug. 17, 2018
Subsequent Event
Subsequent Event [Line Items]
Cash dividends declared per common share	$ 0.11
Cash dividend payable date	Dec. 05, 2018
Cash dividends declared, record date	Nov. 19, 2018