Commitments and Credit Risk - Commitments to fund fixed rate loans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Commitments and Credit Risk
Commitments to fund fixed-rate loans	$ 3,917,445	$ 2,566,950
Commitments to fund fixed-rate loans, Minimum interest rate	3.50%	4.625%
Commitments to fund fixed-rate loans, Maximum interest rate	5.125%	6.00%