Intangible Assets (Intangibles - Future Amortization) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
2013	$ 27,601
2014	20,842
2015	15,612
2016	10,464
2017	8,377
Thereafter	17,470
Total aggregate amortization of intangible assets and liabilities	100,366
Weighted average remaining lease term (in years)	20 years
Below Market Rents [Member]
Finite-Lived Intangible Assets [Line Items]
2013	(10,470)
2014	(8,715)
2015	(8,091)
2016	(6,910)
2017	(6,271)
Thereafter	(23,409)
Total aggregate amortization of intangible assets and liabilities	(63,866)
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	(2,335)
Total aggregate amortization of intangible assets and liabilities	(2,610)
Weighted average remaining lease term (in years)	50 years
Below Market Ground Lease [Member]
Finite-Lived Intangible Assets [Line Items]
2013	42
2014	42
2015	42
2016	42
2017	42
Thereafter	1,470
Total aggregate amortization of intangible assets and liabilities	1,680
Weighted average remaining lease term (in years)	41 years
Above Market Rents [Member]
Finite-Lived Intangible Assets [Line Items]
2013	2,622
2014	2,042
2015	1,884
2016	1,474
2017	1,147
Thereafter	3,163
Total aggregate amortization of intangible assets and liabilities	12,332
Weighted average remaining lease term (in years)	7 years
In Place Leases [Member]
Finite-Lived Intangible Assets [Line Items]
2013	35,462
2014	27,528
2015	21,832
2016	15,913
2017	13,514
Thereafter	38,581
Total aggregate amortization of intangible assets and liabilities	$ 152,830
Weighted average remaining lease term (in years)	8 years