Noncontrolling Interests - Variable interest entity (Details) - Accounting Standards Update ("ASU") 2015-02 - Consolidation (Topic 810): Amendments to the Consolidation Analysis - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Variable interest entity
Net real estate	$ 3,003,824	$ 3,033,180
Total assets	3,466,298	3,529,667
Total debt	241,176	389,105
Total liabilities	$ 327,826	$ 478,955