Mortgage Revenue Bonds - Schedule of MRBs Acquisitions (Parenthetical) (Details) - Mortgage Revenue Bonds [Member] - Ocotillo Springs [Member] - Brawley, CA [Member]	Dec. 31, 2020 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Maximum amount committed to fund	$ 15,000,000.0
Maximum balance of mortgage revenue bonds after stabilization	$ 3,500,000
LIBOR [Member]
Schedule Of Available For Sale Securities [Line Items]
Variable interest rate	3.25%
Floor rate	4.55%
Fixed interest rate	4.35%