Subsequent Events - Additional Information (Detail)	9 Months Ended
Sep. 30, 2017 $ / shares
Dividends Payable [Line Items]
Dividend declared, per share	$ 0.38
Dividend declared, declaration date	Oct. 23, 2017
Dividend declared, payable date	Dec. 12, 2017
Dividend declared, record date	Nov. 21, 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

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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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