Related Party Transactions - Summary of Components of Due to Affiliates (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Due to affiliates	$ 73,768	$ 63,341
Accrued Stockholder Servicing Fee
Related Party Transaction [Line Items]
Due to affiliates	65,348	44,086
Advanced Organization And Offering Costs
Related Party Transaction [Line Items]
Due to affiliates	6,194	7,290
Performance Participation Allocation
Related Party Transaction [Line Items]
Due to affiliates	46	10,366
Accrued Management Fee
Related Party Transaction [Line Items]
Due to affiliates	1,736	1,037
Accrued Affiliate Service Provider Expenses
Related Party Transaction [Line Items]
Due to affiliates	246	112
Advanced Operating Expenses
Related Party Transaction [Line Items]
Due to affiliates	$ 198	$ 450