Intangible Assets and Liabilities and Goodwil (Details 1) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013
Below-market rent
Lease intangible:
Acquired intangible assets/liability weighted-average life	20 years 3 months 18 days
Amortizable Intangible Liabilities
Finite lived intangible liability acquired	$ (31,098)
Acquired intangible assets/liability weighted-average life	20 years 3 months 18 days
In-place lease
Lease intangible:
Finite-lived intangible assets acquired	54,921
Acquired intangible assets/liability weighted-average life	10 years 10 months 24 days
Amortizable Intangible Liabilities
Acquired intangible assets/liability weighted-average life	10 years 10 months 24 days
Above-market rent
Lease intangible:
Finite-lived intangible assets acquired	10,195
Acquired intangible assets/liability weighted-average life	17 years 6 months
Amortizable Intangible Liabilities
Acquired intangible assets/liability weighted-average life	17 years 6 months
Below-market ground lease
Lease intangible:
Finite-lived intangible assets acquired	$ 725
Acquired intangible assets/liability weighted-average life	48 years 3 months 18 days
Amortizable Intangible Liabilities
Acquired intangible assets/liability weighted-average life	48 years 3 months 18 days