Hurricane Related (Recoveries)/Charges, Net (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 New York Properties [Member]	Jun. 30, 2013 New York Properties [Member]	Dec. 31, 2012 New York Properties [Member] Apartment_Homes	Jun. 30, 2013 Hurricane Sandy [Member]	Jun. 30, 2013 Hurricane Sandy [Member] Business Interruption [Member]	Jun. 30, 2013 Hurricane Sandy [Member] Business Interruption [Member]	Jun. 30, 2013 Hurricane Sandy [Member] FY 2012 [Member] Business Interruption [Member]	Jun. 30, 2013 Hurricane Sandy [Member] FY 2013 [Member] Business Interruption [Member]
Number of Communities Owned							3
Number of Apartments Owned							1,706
Impairment of Long-Lived Assets Held-for-use					$ 0	$ 0	$ 9,000
Other Cost and Expense, Operating	1,807	1,434	3,450	2,817			10,400
Total Estimated Insurance Recovery								14,500
Proceeds from Insurance Settlement, Operating Activities									500	3,000	2,800	187
Insurance Recoveries	$ (2,772)	$ 0	$ (5,793)	$ 0