Real Estate and Loans Receivable - Schedule of Unaudited Supplemental Pro Forma Operating Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Acquisition, Pro Forma Information [Abstract]
Total revenues	$ 134,776	$ 135,734	$ 414,632	$ 404,760
Net income	$ 54,332	$ 64,303	$ 193,413	$ 157,910
Net income per share/unit - diluted	$ 0.23	$ 0.27	$ 0.81	$ 0.67

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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