Equity Method Investments in Real Estate Ventures at Fair Value - Schedule of Investments in Real Estate Ventures (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Equity Method Investment and Joint Venture, Fair Value Change [Roll Forward]
Fair value investments, starting balance			$ 8,421
Distributions			(1,322)	$ (100)
Change in fair value of equity method investment	$ 46	$ 606	134	$ 606
Fair value investments, ending balance	$ 6,965		$ 6,965

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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