Intangible Assets (Intangibles - Future Amortization) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
Finite-Lived Intangible Assets [Line Items]
2013	$ 16,278
2014	12,653
2015	10,220
2016	7,158
2017	5,541
Thereafter	9,526
Total aggregate amortization of intangible assets and liabilities	61,376
Below Market Rents [Member]
Finite-Lived Intangible Assets [Line Items]
2013	(9,020)
2014	(8,569)
2015	(7,793)
2016	(7,314)
2017	(5,427)
Thereafter	(18,969)
Total aggregate amortization of intangible assets and liabilities	$ (57,092)
Weighted average remaining lease term (in years)	9 years
Above Market Ground Lease [Member]
Finite-Lived Intangible Assets [Line Items]
2013	$ (55)
2014	(55)
2015	(55)
2016	(55)
2017	(55)
Thereafter	(2,225)
Total aggregate amortization of intangible assets and liabilities	$ (2,500)
Weighted average remaining lease term (in years)	48 years
Above Market Rents [Member]
Finite-Lived Intangible Assets [Line Items]
2013	$ 1,843
2014	1,384
2015	1,305
2016	883
2017	734
Thereafter	1,882
Total aggregate amortization of intangible assets and liabilities	$ 8,031
Weighted average remaining lease term (in years)	7 years
In Place Leases [Member]
Finite-Lived Intangible Assets [Line Items]
2013	$ 23,510
2014	19,893
2015	16,763
2016	13,644
2017	10,289
Thereafter	28,838
Total aggregate amortization of intangible assets and liabilities	$ 112,937
Weighted average remaining lease term (in years)	7 years