Investments in Unconsolidated Real Estate Funds - Schedule of Combined Financial Information of Unconsolidated Real Estate Funds (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Investment Holdings [Line Items]
Other assets	$ 95,031	$ 91,552
Total assets	1,662,208	1,426,199
Other liabilities	23,758	22,310
Total liabilities	1,052,374	910,192
Equity	609,834	516,007
Total liabilities and equity	1,662,208	1,426,199
Unconsolidated Real Estate Funds [Member]
Investment Holdings [Line Items]
Real estate investments	631,566	645,013
Cash and cash equivalents	1,322	10,791
Other assets	1,933	10
Total assets	634,821	655,814
Other liabilities	11,282	1,483
Total liabilities	11,282	1,483
Equity	623,539	654,331
Total liabilities and equity	$ 634,821	$ 655,814