Real Estate (Details) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended		0 Months Ended	9 Months Ended	0 Months Ended	3 Months Ended
	Jul. 12, 2011	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Jan. 19, 2011 Tower Shops 1/19/11 [Member]	Sep. 30, 2011 Tower Shops 1/19/11 [Member]	Jul. 12, 2011 Feasterville Shopping Center 7/12/11 [Member]	Sep. 30, 2011 Feasterville Shopping Center 7/12/11 [Member]
Business Acquisition Section 1031 Agreement End Date	July 12, 2011
Date of acquisition and consolidation						January 19, 2011
Purchase price of leasehold property						$ 66,100,000
Mortgage loan face amount						41,000,000
Mortgage loan fair value						42,900,000
Leasable area (square feet)						372,000
Acres of real estate property						67
Purchase price allocation, other assets						1,200,000
Purchase price allocation, liabilities						4,400,000
Acquisition costs						400,000	200,000
Maximum period of sale to defer gain on sale of other property, days						180
Proceeds from sale of buildings								20,000,000
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax		$ 14,757,000		$ 14,800,000	$ 1,000,000				$ 14,800,000