RELATED PARTY TRANSACTIONS (Details) (USD $)			3 Months Ended				3 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2012 Lead Trustee [Member]	Mar. 31, 2011 Lead Trustee [Member]	Mar. 31, 2012 Unconsolidated Affiliates [Member]	Dec. 31, 2011 Unconsolidated Affiliates [Member]	Mar. 31, 2012 Core Portfolio [Member] Brandywine Portfolio [Member]	Mar. 31, 2011 Core Portfolio [Member] Brandywine Portfolio [Member]
Related Party Transaction [Line Items]
Related party revenue							$ 200,000	$ 500,000
Receivable from related parties	1,782,000	1,375,000			1,800,000	1,400,000
Related party transaction expense			$ 25,000	$ 25,000