Investment and Mortgage-Backed Securities, Available for Sale (Schedule of Available for Sale Securities) (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Gross Realized Losses	$ 288,000	$ 67,000
Available For Sale Securities Pledged as Collateral, Amortized Cost Basis	145,100,000		$ 111,800,000
Pledged Assets Separately Reported, Other Debt Securities Available-for-sale or Held-for-investment	147,500,000		111,700,000
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	429,828,361		386,296,513
Available-for-sale Securities, Gross Unrealized Gains	9,928,783		3,177,017
Available-for-sale Securities, Gross Unrealized Losses	1,513,709		3,217,693
Available-for-sale Securities, Fair Value Disclosure	438,243,435		386,255,837
Proceeds From Sale of Available For Sale Securities Including Mortgage Backed Securities	70,800,000	28,600,000
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	43,187,057		60,141,164
Available-for-sale Securities, Gross Unrealized Gains	4,329,929		1,518,974
Available-for-sale Securities, Gross Unrealized Losses	0		329,769
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	25,100,000		29,700,000
Available-for-sale Securities, Fair Value Disclosure	25,400,000
Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Gross Realized Gains	1,300,000	$ 503,000	20,713
Collateralized Loan Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	41,569,303		12,934,037
Available-for-sale Securities, Gross Unrealized Losses	329,972		69,249
Available-for-sale Securities, Gross Realized Gains	4,007
SBA Bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	120,910,755		125,777,016
Available-for-sale Securities, Gross Unrealized Gains	717,658		560,352
Available-for-sale Securities, Gross Unrealized Losses	651,988		890,837
Mortgage-Backed Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	221,931,218		185,291,038
Available-for-sale Securities, Gross Unrealized Gains	4,836,297		1,073,432
Available-for-sale Securities, Gross Unrealized Losses	494,126		1,903,919
Equity Securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	155,000		155,000
Available-for-sale Securities, Gross Unrealized Gains	0		0
Available-for-sale Securities, Gross Unrealized Losses	0		0
Taxable Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost of Investment And Mortgage-Backed Securities Available For Sale	2,013,786		1,998,258
Available-for-sale Securities, Gross Unrealized Gains	40,892		3,546
Available-for-sale Securities, Gross Unrealized Losses	37,623		23,919
Fair Value, Measurements, 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	47,516,986		61,330,369
Fair Value, Measurements, 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	41,243,338		12,885,501
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| SBA Bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Fair Value Disclosure	120,976,425		125,446,531
Fair Value, Measurements, 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	226,273,389		184,460,551
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Equity Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Fair Value Disclosure	155,000		155,000
Fair Value, Measurements, 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	$ 2,017,055		$ 1,977,885

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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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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