Noncontrolling Interests - Variable interest entity (Details) - Accounting Standards Update ("ASU") 2015-02 - Consolidation (Topic 810): Amendments to the Consolidation Analysis - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Variable interest entity
Net real estate	$ 3,040,903	$ 3,082,025
Total assets	3,499,481	3,586,239
Total debt	251,047	393,812
Total liabilities	$ 364,797	$ 511,476