Consideration Transferred to Acquire Real Estate Properties (Detail) (Series of Individually Immaterial Business Acquisitions, USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2013
Series of Individually Immaterial Business Acquisitions
Fair value of consideration transferred:
Non-cash increase in investments in real estate from the conversion of loans	$ 36,950
Other considerations	123
Total fair value of consideration transferred	$ 37,073

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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