Loans Payable - Schedule of Future Principal Payment Due under Loan Agreements (Detail) - UBS AG, CCRE, Citigroup Global Markets Realty Corp, Goldman Sachs Bank USA, CBRE Multifamily Capital Inc and Arbor Private Label LLC [Member]	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
2024	$ 63,170,173
Thereafter	247,197,184
Total	$ 310,367,357