Mortgage Revenue Bonds - Additional Information (Details)	3 Months Ended
Mar. 31, 2020 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Provision for credit loss	$ 1,357,681
Provision Center 2014-1 [Member]
Schedule Of Available For Sale Securities [Line Items]
Provision for credit loss	$ 1,400,000

Amount of expense related to estimated loss from loan and lease transactions.

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