Investments in and Advances to Joint Ventures - Condensed Combined Statements of Operations of Unconsolidated Joint Venture Investments (Parenthetical) (Detail) (USD $)			9 Months Ended
Sep. 30, 2013	Aug. 31, 2013	Sep. 30, 2013 Coventry II Fund JV [Member]
Schedule of Equity Method Investments [Line Items]
Investment Percentage in joint venture		5.00%	20.00%
Loss on property transfer			$ 32,600,000
Joint venture net loss attributable to company			0
Investment basis Value For which No Income Loss Recognized	0
Obligation or Intent to fund additional capital	$ 0

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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Balance Type:	na
Period Type:	instant