Investment and Mortgage-Backed Securities, Available for Sale (Schedule of Held to Maturity Securities, Contractual Maturities) (Details)	Mar. 31, 2021 USD ($)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Less Than One Year, Amortized Cost	$ 232,575
One – Five Years, Amortized Cost	7,559,449
Five – Ten Years, Amortized Cost	76,244,391
After Ten Years, Amortized Cost	217,909,220
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	558,836,046
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Less Than One Year, Fair Value	225,958
One – Five Years, Fair Value	7,569,728
Five – Ten Years, Fair Value	76,517,484
After Ten Years, Fair Value	221,680,571
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	$ 568,787,583

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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