Organization And Summary Of Significant Accounting Policies (Narrative) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 years	Dec. 31, 2010	Dec. 31, 2009
Organization And Significant Accounting Policies [Line Items]
Number of units in real estate property	21,658
Number of real estate properties	58
Common stock, shares outstanding	52,988,000	48,913,000
Minority interest in the ownership percentage	0.30%
Common units held by persons other than the company	156
Ownership interest in the operating partnership	99.70%
Operating leases term (in years)	1
Revenue recognized lease (in years)	1
Weighted average common ownership interest, percentage	$ 99.70%	$ 99.70%	$ 99.60%
Weighted average borrowing costs, percentage	6.00%	6.30%	6.30%
Development or construction costs	$ 2,854	$ 719	$ 3,889
Investment maturity period maximum (in months)	three
Atlanta, Georgia [Member]
Organization And Significant Accounting Policies [Line Items]
Concentration of location for communities, percentage	34.30%
Dallas, Texas [Member]
Organization And Significant Accounting Policies [Line Items]
Concentration of location for communities, percentage	23.50%
Washington, D.C. [Member]
Organization And Significant Accounting Policies [Line Items]
Concentration of location for communities, percentage	12.80%
Tampa, Florida [Member]
Organization And Significant Accounting Policies [Line Items]
Concentration of location for communities, percentage	10.50%
Buildings And Components [Member]
Organization And Significant Accounting Policies [Line Items]
Estimated useful life (in years)	40
Other Building And Land Improvements [Member]
Organization And Significant Accounting Policies [Line Items]
Estimated useful life (in years)	20
Furniture, Fixtures And Equipment [Member]
Organization And Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life, Maximum	10
Estimated useful life, minimum (in years)	5
Estimated useful life, maximum (in years)	10
Held In Unconsolidated Entities [Member]
Organization And Significant Accounting Policies [Line Items]
Number of units in real estate property	1,747
Number of real estate properties	5
Under Development [Member]
Organization And Significant Accounting Policies [Line Items]
Number of units in real estate property	1,568
Number of real estate properties	5
For-Sale Condominium Homes [Member]
Organization And Significant Accounting Policies [Line Items]
Number of real estate properties	2
Residential Leases [Member]
Organization And Significant Accounting Policies [Line Items]
Average remaining lease term, Minimum	6
Average remaining lease term, Maximum	12
Retail Leases [Member]
Organization And Significant Accounting Policies [Line Items]
Average remaining lease term, Minimum	5
Average remaining lease term, Maximum	10