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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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+ 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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Equity - Dividends Per Share and Distribution Per Unit Declared (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Dividends Payable [Line Items]
Dividend Per Share/Distribution Per Unit	$ 0.68	$ 0.64	$ 0.40
Installment 1-FY2015 [Member]
Dividends Payable [Line Items]
Declaration Date	Jan. 28, 2015
Record Date	Apr. 01, 2015
Paid Date	Apr. 09, 2015
Dividend Per Share/Distribution Per Unit	$ 0.17
Installment 2-FY2015 [Member]
Dividends Payable [Line Items]
Declaration Date	May 08, 2015
Record Date	Jul. 01, 2015
Paid Date	Jul. 09, 2015
Dividend Per Share/Distribution Per Unit	$ 0.17
Installment 3-FY2015 [Member]
Dividends Payable [Line Items]
Declaration Date	Aug. 06, 2015
Record Date	Oct. 01, 2015
Paid Date	Oct. 08, 2015
Dividend Per Share/Distribution Per Unit	$ 0.17
Installment 4-FY2015 [Member]
Dividends Payable [Line Items]
Declaration Date	Nov. 06, 2015
Record Date	Dec. 31, 2015
Paid Date	Jan. 07, 2016
Dividend Per Share/Distribution Per Unit	$ 0.17
Installment 1-FY2014 [Member]
Dividends Payable [Line Items]
Declaration Date		Feb. 18, 2014
Record Date		Apr. 01, 2014
Paid Date		Apr. 10, 2014
Dividend Per Share/Distribution Per Unit		$ 0.16
Installment 2-FY2014 [Member]
Dividends Payable [Line Items]
Declaration Date		May 09, 2014
Record Date		Jul. 01, 2014
Paid Date		Jul. 10, 2014
Dividend Per Share/Distribution Per Unit		$ 0.16
Installment 3-FY2014 [Member]
Dividends Payable [Line Items]
Declaration Date		Aug. 04, 2014
Record Date		Oct. 01, 2014
Paid Date		Oct. 09, 2014
Dividend Per Share/Distribution Per Unit		$ 0.16
Installment 4-FY2014 [Member]
Dividends Payable [Line Items]
Declaration Date		Nov. 10, 2014
Record Date		Dec. 30, 2014
Paid Date		Jan. 08, 2015
Dividend Per Share/Distribution Per Unit		$ 0.16
Installment 1-FY2013 [Member]
Dividends Payable [Line Items]
Declaration Date			Jun. 19, 2013
Record Date			Jul. 01, 2013
Paid Date			Jul. 11, 2013
Dividend Per Share/Distribution Per Unit			$ 0.08
Installment 2-FY2013 [Member]
Dividends Payable [Line Items]
Declaration Date			Aug. 09, 2013
Record Date			Oct. 01, 2013
Paid Date			Oct. 10, 2013
Dividend Per Share/Distribution Per Unit			$ 0.16
Installment 3-FY2013 [Member]
Dividends Payable [Line Items]
Declaration Date			Nov. 11, 2013
Record Date			Dec. 30, 2013
Paid Date			Jan. 09, 2014
Dividend Per Share/Distribution Per Unit			$ 0.16