Supplemental Detail for Certain Components of Consolidated Balance Sheets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Other assets, net
Value of in-place leases, net	$ 206,313	$ 123,255
Value of above-market leases, net	35,812	30,081
Loans receivable	35,126	2,178
Notes receivable issued in connection with property sales	19,300	19,401
Prepaid expenses	9,489	9,833
Notes receivable acquired in connection with an acquisition	8,780	8,780
Restricted escrow deposits	1,805	50
Corporate assets, net	909	849
Other items	424	2,107
Total other assets	357,374	222,635
Bond
Other assets, net
Deferred financing costs, net	29,687	22,209
Credit Facility
Other assets, net
Deferred financing costs, net	8,188	3,141
Mortgages
Other assets, net
Deferred financing costs, net	$ 1,541	$ 751