Segment Reporting - Summary of Total Assets by Segment (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total assets	$ 1,934,598	$ 200
Multifamily [Member]
Segment Reporting Information [Line Items]
Total assets	932,689
Industrial [Member]
Segment Reporting Information [Line Items]
Total assets	456,639
Hotel [Member]
Segment Reporting Information [Line Items]
Total assets	102,225
Retail [Member]
Segment Reporting Information [Line Items]
Total assets	56,780
Real Estate-Related Securities [Member]
Segment Reporting Information [Line Items]
Total assets	292,074
Other (Corporate) [Member]
Segment Reporting Information [Line Items]
Total assets	$ 94,191