Investment and Mortgage-Backed Securities, Available for Sale (Schedule of Available for Sale Securities) (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Gross Realized Losses	$ 0	$ 8,000
Available For Sale Securities Pledged as Collateral, Amortized Cost Basis	204,500,000		$ 171,400,000
Pledged Assets Separately Reported, Other Debt Securities Available-for-sale or Held-for-investment	210,500,000		173,100,000
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	466,246,618		408,695,280
Available-for-sale Securities, Gross Unrealized Gains	10,522,442		8,410,493
Available-for-sale Securities, Gross Unrealized Losses	7,444,855		2,460,933
Available-for-sale Securities, Fair Value Disclosure	469,324,205		414,644,840
Proceeds From Sale of Available For Sale Securities Including Mortgage Backed Securities	11,100,000	6,600,000
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	36,159,875		43,153,086
Available-for-sale Securities, Gross Unrealized Gains	4,115,386		4,088,408
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	28,000,000		15,800,000
Available-for-sale Securities, Fair Value Disclosure	27,100,000
Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Gross Realized Gains	707,000	$ 299,000	0
Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	51,954,147		41,088,231
Available-for-sale Securities, Gross Unrealized Losses	4,154,233		856,401
Available-for-sale Securities, Gross Realized Gains	0
SBA Bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	116,275,454		111,927,938
Available-for-sale Securities, Gross Unrealized Gains	677,769		622,105
Available-for-sale Securities, Gross Unrealized Losses	598,900		656,944
Mortgage-Backed Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	233,945,687		197,356,288
Available-for-sale Securities, Gross Unrealized Gains	5,622,860		3,664,621
Available-for-sale Securities, Gross Unrealized Losses	2,188,024		582,902
Taxable Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	27,911,455		15,169,737
Available-for-sale Securities, Gross Unrealized Gains	106,427		35,359
Available-for-sale Securities, Gross Unrealized Losses	503,698		364,686
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	40,275,261		47,241,494
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	47,799,914		40,231,830
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	116,354,323		111,893,099
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	237,380,523		200,438,007
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	$ 27,514,184		$ 14,840,410

Available For Sale Securities Pledged as Collateral, Amortized Cost Basis

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Proceeds From Sale of Available For Sale Securities Including Mortgage Backed Securities

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

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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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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-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
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