Supplemental Detail for Certain Components of Consolidated Balance Sheets - Accounts Payable, Acquired Lease Intangibles, and Other Liabilities (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) item	Jan. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Aug. 31, 2016 USD ($)
Accounts payable and accrued expenses
Property taxes payable	$ 22,455		$ 16,949
Accrued costs on properties under development	4,235		9,049
Mortgages, term loans, credit line - interest payable and interest rate swaps	3,793		5,432
Other items	20,663		29,058
Total accounts payable and accrued expenses	92,947		121,156
Acquired lease intangible liabilities, net
Acquired below-market leases	340,504		318,926
Accumulated amortization of acquired below-market leases	(68,127)		(54,720)
Total acquired lease intangible liabilities, net	272,377		264,206
Other liabilities
Rent received in advance and other deferred revenue	103,520		74,098
Security deposits	6,268		6,502
Capital lease obligations	5,249		5,016
Total other liabilities	115,037		85,616
Additional rent	$ 75,000
Number of installments | item	2
Deferred revenue relating to lease modification		$ 37,500		$ 37,500
Remaining lease term	15 years
Notes Payable
Accounts payable and accrued expenses
Interest payable	$ 41,801		$ 60,668