Acquisition of Rental Property Schedule of Purchase Price Allocation (Details) (Prime Outlets at Jeffersonville [Member], USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2011
Business Acquisition [Line Items]
Land	$ 2,752
Business Acquisition, Purchase Price Allocation, Property	109,843
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	21,405
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net	134,000
Leases, Acquired-in-Place, Market Adjustment [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	1,958
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life	7.2
Leases, Acquired-in-Place [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	8,224
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life	3.7
Tenant Relationships [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	10,029
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life	7.8
Lease and Legal Costs [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets	$ 1,194
Acquired Finite-lived Intangible Asset, Weighted Average Useful Life	4.9