Noncontrolling Interests - Variable Interest Entities (Details) - VIE, Primary Beneficiary, Aggregated Disclosure - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Variable interest entity
Net real estate	$ 2,903,093	$ 2,936,397
Total assets	3,259,495	3,342,443
Total debt	191,565	210,384
Total liabilities	$ 320,800	$ 313,295