Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Intangible Assets
In-place leases, net of accumulated amortization of $51,957 and $26,239 in 2014 and 2013, respectively	$ 127,624	$ 152,830
Above-market tenant leases, net of accumulated amortization of $12,990 and $11,284 in 2014 and 2013, respectively	9,929	12,332
Below-market ground lease, net of accumulated amortization of $0 and $21 in 2014 and 2013, respectively	0	1,680
Goodwill	4,057	4,131	4,147	4,751
Intangible Assets, Net (Including Goodwill)	141,610	170,973
In-place leases accumulated amortization	51,957	26,239
Above-market tenant leases accumulated amortization	12,990	11,284
Below-market ground lease accumulated amortization	$ 0	$ 21