Operating Segments to the corresponding amounts in Narrative (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment assets,	$ 913,393	$ 960,342	$ 1,109,749
Investments in real estate partnerships,	8,168	10,746	12,491
Other assets and receivables,	196,744	197,032	209,360
Assets held for sale,	17,040	67,351	225,674
Total Consolidated Assets	$ 1,135,345	$ 1,235,471	$ 1,557,274