Supplemental Detail for Certain Components of Consolidated Balance Sheets (Details 4) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Accounts payable and accrued expenses
Accrued costs on properties under development	$ 9,430	$ 8,595
Other items	23,228	21,122
Total accounts payable and accrued expenses	77,411	70,426
Acquired lease intangible liabilities, net
Acquired below-market leases	123,141	28,975
Accumulated amortization of acquired below-market leases	(6,760)	(2,504)
Acquired lease intangible liabilities	116,381	26,471
Other liabilities
Rent received in advance	16,809	20,929
Preferred units issued upon acquisition of ARCT	6,750
Security deposits	5,707	5,130
Total other liabilities	29,266	26,059
Note
Accounts payable and accrued expenses
Interest payable	41,790	40,061
Mortgages
Accounts payable and accrued expenses
Interest payable	$ 2,963	$ 648