Investment and Mortgage-Backed Securities, Held to Maturity (Schedule of investment and mortgage-backed securities held to maturity) (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity, gross unrealized gains	$ 729,574	$ 984,015
Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment	22,420,739	18,254,394
Held to maturity, gross unrealized losses	296,370	33,122
Debt Securities, Held-to-maturity, Fair Value	22,853,943	19,205,287
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	22,420,739	18,254,394
Held to maturity, gross unrealized gains	729,574	984,015
Held to maturity, gross unrealized losses	296,370	33,122
Debt Securities, Held-to-maturity, Fair Value	$ 22,853,943	$ 19,205,287