RELATED PARTY TRANSACTIONS (Details) (USD $)			3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Lead Trustee	Sep. 30, 2011 Lead Trustee	Sep. 30, 2012 Lead Trustee	Sep. 30, 2011 Lead Trustee	Sep. 30, 2012 Unconsolidated Affiliates	Dec. 31, 2011 Unconsolidated Affiliates	Sep. 30, 2012 Core Portfolio Brandywine Portfolio	Sep. 30, 2011 Core Portfolio Brandywine Portfolio	Sep. 30, 2012 Core Portfolio Brandywine Portfolio	Sep. 30, 2011 Core Portfolio Brandywine Portfolio
Related Party Transaction [Line Items]
Related party revenue									$ 200,000	$ 200,000	$ 600,000	$ 800,000
Receivable from related parties	0	1,375,000					900,000	1,400,000
Related party transaction expense			$ 25,000	$ 25,000	$ 75,000	$ 75,000