Investments in Unconsolidated Real Estate Entities - Summary of Financial Information for Apartment LLCs (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Real Estate Properties [Line Items]
Investments in unconsolidated real estate entities	$ 15,873	$ 16,624
Accumulated depreciation, assets held for sale	1,023,652	937,310
Unconsolidated Properties [Member]
Real Estate Properties [Line Items]
Investments in unconsolidated real estate entities	15,873	16,624
Accumulated depreciation, assets held for sale	$ 54,936	$ 49,153

The aggregate amount of liabilities as of the balance sheet date for obligations incurred in connection with the entity's investments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

The cumulative amount of depreciation for real estate property held for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(3))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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