Identified Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross amount	$ 415,261	$ 424,976
Accumulated amortization	(187,360)	(199,821)
Net	227,901	225,155
Gross amount	643,488	657,976
Accumulated amortization	(325,340)	(329,775)
Net	318,148	328,201
Below Market Leases Net Of Above Market Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	78,749	37,516	$ 41,970
2016	52,359
2017	44,501
2018	43,028
2019	31,011
2020	23,320
Other Identified Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	36,659	28,275	61,915
2016	29,349
2017	24,427
2018	20,063
2019	15,779
2020	12,345
Tenant Under Ground Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	1,832	$ 1,832	$ 2,745
2016	1,832
2017	1,832
2018	1,832
2019	1,832
2020	$ 1,832