Investment and Mortgage-Backed Securities, Available for Sale (Schedule of Held to Maturity Securities, Contractual Maturities) (Details)	Mar. 31, 2022 USD ($)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Less Than One Year, Amortized Cost	$ 534,371
One – Five Years, Amortized Cost	6,267,665
Five – Ten Years, Amortized Cost	85,826,597
After Ten Years, Amortized Cost	217,031,877
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	687,898,352
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Less Than One Year, Fair Value	539,925
One – Five Years, Fair Value	6,218,626
Five – Ten Years, Fair Value	84,508,438
After Ten Years, Fair Value	211,981,778
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	$ 668,057,963

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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