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

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

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.

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Subsequent Events - Additional Information (Detail) - $ / shares		3 Months Ended												12 Months Ended
	Jan. 23, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Subsequent Event [Line Items]
Dividends per share declared on outstanding common stock		$ 0.27	$ 0.14	$ 0.14	$ 0.14	$ 0.27	$ 0.12	$ 0.12	$ 0.12	$ 0.25	$ 0.10	$ 0.10	$ 0.10	$ 0.69	$ 0.63	$ 0.55
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends per share declared on outstanding common stock	$ 0.14
Dividend payable date	Mar. 02, 2017
Dividends payable, shareholders record date	Feb. 17, 2017