Summary of Significant Accounting Policies - Revenues - Accounts Receivables (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) joint_venture	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Tenant Receivables	$ 14,521	$ 10,583
Document Fiscal Year Focus	2015
Current Fiscal Year End Date	--12-31
Number of Joint Ventures, Unilateral Dissolution Right | joint_venture	5
Provision for doubtful accounts	$ 2,364	2,192	$ 1,841
Accrued CAM, insurance and tax reimbursements receivables	12,358	15,369
Other receivables	10,708	9,570
Less: allowance for doubtful accounts	(5,295)	(4,523)
Accounts Receivable, Net	$ 32,292	30,999
Percentage Of Revenue By Customer	5.00%
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage Of Revenue By Customer	5.00%
Discontinued operations
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for doubtful accounts	$ 0	$ 0	$ 53