Investment and Mortgage-Backed Securities, Available for Sale (Schedule of Held to Maturity Securities, Contractual Maturities) (Details)	Sep. 30, 2021 USD ($)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Less Than One Year, Amortized Cost	$ 74,883
One – Five Years, Amortized Cost	7,092,198
Five – Ten Years, Amortized Cost	82,618,930
After Ten Years, Amortized Cost	218,310,044
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	617,131,400
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Less Than One Year, Fair Value	70,483
One – Five Years, Fair Value	7,092,980
Five – Ten Years, Fair Value	83,552,707
After Ten Years, Fair Value	223,501,351
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	$ 627,833,669

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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