Other Assets (Intangibles - Future Amortization) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
2013	$ 4,865
2014	4,356
2015	3,815
2016	3,314
2017	2,284
Thereafter	7,347
Total aggregate amortization of intangible assets and liabilities	25,981
Weighted average remaining lease term (in years)	10 years
Below Market Rents [Member]
Finite-Lived Intangible Assets [Line Items]
2013	(363)
2014	(340)
2015	(326)
2016	(276)
2017	(183)
Thereafter	(391)
Total aggregate amortization of intangible assets and liabilities	(1,879)
Weighted average remaining lease term (in years)	6 years
Above Market Ground Lease [Member]
Finite-Lived Intangible Assets [Line Items]
2013	(9)
2014	(9)
2015	(9)
2016	(9)
2017	(9)
Thereafter	(624)
Total aggregate amortization of intangible assets and liabilities	(669)
Weighted average remaining lease term (in years)	74 years
Above Market Rents [Member]
Finite-Lived Intangible Assets [Line Items]
2013	1,062
2014	1,048
2015	978
2016	910
2017	651
Thereafter	2,243
Total aggregate amortization of intangible assets and liabilities	6,892
Weighted average remaining lease term (in years)	8 years
In Place Leases [Member]
Finite-Lived Intangible Assets [Line Items]
2013	4,175
2014	3,657
2015	3,172
2016	2,689
2017	1,825
Thereafter	6,119
Total aggregate amortization of intangible assets and liabilities	$ 21,637
Weighted average remaining lease term (in years)	7 years