Assets Held for Sale and Discontinued Operations (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 Units Property	Dec. 31, 2012 Units Property	Dec. 31, 2011 Units Property
Discontinued Operations And Assets Held For Sale (Textual) [Abstract]
Number of apartment communities to be sold period for evaluation	12 months
Number of consolidated apartment communities sold	29	75	67
Number of units in consolidated apartment communities sold	6,953	11,232	10,912
Prepayment penalties treated as reduction of gain upon repayment of property debt collateralized by apartment communities sold	$ 16.5	$ 16.5	$ 14.9
Assets Held-for-sale [Member]
Long Lived Assets Held-for-sale [Line Items]
Number of apartment communities	0	29
Number of homes in apartment communities		6,953