Legal Proceedings (Details) (USD $)	12 Months Ended									3 Months Ended	12 Months Ended
	Dec. 31, 2006	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2012 UCO Litigation	Dec. 31, 2011 UCO Litigation	Jan. 31, 2008 UCO Litigation	Mar. 31, 2012 UCO Litigation Post-trial Motion - Amendment	Dec. 31, 2011 UCO UCO Litigation	Dec. 31, 2011 Colonial Properties Trust UCO Litigation	Jun. 30, 2010 Colonial Grand at Traditions	Dec. 31, 2011 Colonial Grand at Traditions	Jun. 30, 2012 Colonial Grand at Traditions	Jun. 17, 2011 Colonial Grand at Traditions	Apr. 30, 2007 Colonial Grand at Traditions	Jun. 30, 2012 Colonial Grand at Traditions Colonial Properties Trust	Jun. 30, 2012 Colonial Grand at Traditions Joint Venture partner	Apr. 30, 2007 Colonial Grand at Traditions Financial Guarantee	Apr. 30, 2007 Colonial Grand at Traditions Financial Guarantee Colonial Properties Trust	Apr. 30, 2007 Colonial Grand at Traditions Financial Guarantee Joint Venture partner
Legal
Guarantor obligations, maximum exposure																	$ 7,000,000	$ 3,500,000	$ 3,500,000
Equity method investment, ownership percentage															35.00%	65.00%
Construction loan														34,100,000
Loans payable to bank													35,500,000
Debt instrument, maturity date										Apr. 15, 2010
Payment to acquire outstanding note											21,100,000
Amount of potential loss due to pending litigation						10,300,000	4,800,000					13,000,000
Loss contingency, minimum possible loss												0
Loss contingency, maximum possible loss												13,000,000
For-sale residential unit dispositions	230
Number of for-sale projects				5
Compensatory damages awarded								4,800,000	500,000
Estimated litigation liability					3,300,000
Loss contingency accrual, at carrying value		$ 8,900,000	$ 8,800,000