Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] - Dividend Declared [Member]	Jul. 31, 2018 $ / shares
Subsequent Event [Line Items]
Date of declared to shareholders entitled to dividends	Jul. 31, 2018
Cash dividend per share	$ 0.22
Date of payment to shareholders entitled to dividends	Sep. 21, 2018
Date of record of shareholders entitled to dividends	Sep. 07, 2018

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

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

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

+ References

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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

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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

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