The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04.16(b))
-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04.16(a))
-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

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Balance Type:	na
Period Type:	instant

Commitments and Contingencies (Details) - USD ($) $ in Thousands		6 Months Ended
	Feb. 12, 2016	Jun. 30, 2016	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
downREIT operating partnership units, outstanding		768,765
downREIT operating partnership units outstanding, fair value		$ 127,300
Redeemable Noncontrolling Interest [Line Items]
Redemption price of noncontrolling interest		$ 13,023	$ 0
Galaxy/Hollywood
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling interest percent acquired	10.00%
Redemption price of noncontrolling interest	$ 13,000
Effective Interest Acquisition	100.00%