Investment and Mortgage-Backed Securities, Available for Sale (Schedule of Available for Sale Securities) (Details) - USD ($)	3 Months Ended	6 Months Ended
Mar. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Available For Sale Securities Pledged as Collateral, Amortized Cost Basis		$ 297,000,000.0	$ 263,300,000
Pledged Assets Separately Reported, Other Debt Securities Available-for-sale or Held-for-investment		307,800,000	274,400,000
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale		586,101,589	572,137,595
Available-for-sale Securities, Gross Unrealized Gains	$ 19,456,692	16,888,720
Available-for-sale Securities, Gross Unrealized Losses	2,269,886	2,403,202
Available-for-sale Securities, Fair Value Disclosure		600,587,107	589,324,401
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale		44,837,867	42,793,179
Available-for-sale Securities, Gross Unrealized Gains	6,023,263	5,497,373
Available-for-sale Securities, Gross Unrealized Losses	0	0
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale		32,300,000	37,000,000.0
Available-for-sale Securities, Fair Value Disclosure		32,700,000
Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Gross Realized Gains	220,239
Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale		62,009,524	61,244,212
Available-for-sale Securities, Gross Unrealized Losses	382,986	96,097
Available-for-sale Securities, Gross Realized Gains		568,036
SBA Bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale		149,915,729	153,565,023
Available-for-sale Securities, Gross Unrealized Gains	797,456	1,235,895
Available-for-sale Securities, Gross Unrealized Losses	1,057,454	838,557
Mortgage-Backed Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale		277,366,500	267,854,880
Available-for-sale Securities, Gross Unrealized Gains	10,672,412	8,222,917
Available-for-sale Securities, Gross Unrealized Losses	754,278	1,159,523
Taxable Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale		51,971,969	46,680,301
Available-for-sale Securities, Gross Unrealized Gains	1,743,322	1,364,499
Available-for-sale Securities, Gross Unrealized Losses	$ 75,168	309,025
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Fair Value Disclosure		50,335,240	48,816,442
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Fair Value Disclosure		62,481,463	61,081,465
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| SBA Bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Fair Value Disclosure		150,313,067	153,305,025
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Mortgage-Backed Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Fair Value Disclosure		284,429,894	277,773,014
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Taxable Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Fair Value Disclosure		$ 53,027,443	$ 48,348,455

Available For Sale Securities Pledged as Collateral, Amortized Cost Basis

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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-Publisher FASB
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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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The fair value, as of the date of each statement of financial position presented, of other securities, classified as available for sale or held for investment, which are owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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