Deferred Leasing Costs and Acquisition-related Intangible Assets and Liabilities, net (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Deferred Leasing Costs [Member]
Finite-Lived Intangible Assets and Liabilities [Line Items]
Fully amortized deferred leasing costs and intangibles	$ 7.0
Above-Market Leases [Member]
Finite-Lived Intangible Assets and Liabilities [Line Items]
Fully amortized deferred leasing costs and intangibles	0.6
In-Place Leases [Member]
Finite-Lived Intangible Assets and Liabilities [Line Items]
Fully amortized deferred leasing costs and intangibles	10.3
Below Market Leases [Member]
Finite-Lived Intangible Assets and Liabilities [Line Items]
Fully amortized intangible liabilities	$ 4.4