Employee Benefits and Retirement Plans (Details Narrative) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase decrease in accrued pension liability	$ 646,186	$ 721,735	$ 716,622
Changes to other comprehensive income (loss) on pre-tax basis	1,086,510	(32,075)
Increased in fair value of plan assets	$ 632,723
Targeted investment portfolio allocated	45.00%
Investments	$ 300,000,000
Expected contribute from employer	700,000	460,000	480,000
Estimated amortization amounts, net loss	504,825
Expense incurred	(114,386)	(412,047)	129,086
Pension Plan 2020 [Member]
Expected contribute from employer	500,000
Southwest Georgia Bank 401(K) Plan [Member]
Employee contributions	206,731	219,006	204,565
Employee Stock Ownership Plan [Member]
Expected contribute from employer	$ 450,000	475,000	425,000
ESOP holds Corporation's outstanding common stock	251,119
Number of shares are allocated to participants	201,780
Unreleased shares are pledged as collateral	49,339
Long-term debt incurred from repurchasing participants' shares	$ 911,718
Directors and Executive Officers Stock Purchase Plan [Member]
Employee contributions	900
Expense incurred	$ 248,780	$ 248,800	$ 265,900
Dividend Reinvestment and Share Purchase Plan [Member]
Reinvestment of common stock dividends, voluntary cash payments description	Not less than $5 nor more than $5,000 per month
Shares issued through the plan	5,986	5,726	5,286
Shares issued at an average price per share	$ 20.96	$ 22.63	$ 21.18
2013 Omnibus Incentive Plan [Member]
Common stock authorized for issuance	125,000
Stock options exercise period	5 years
Incentive Plan [Member]
Number of restricted stock awards shares granted during the period	4,456	13,316	4,271
Restricted stock awards vested		2,606	714
Restricted stock awards, repurchased	349
Incentive Plan [Member] \| 2018 [Member]
Restricted stock awards forfeited	1,163
Incentive Plan [Member] \| 2017 [Member]
Restricted stock awards forfeited	559
Equity Securities [Member]
Targeted investment portfolio allocated	20.00%
Minimum [Member]
Targeted investment portfolio allocated	50.00%
Maximum [Member]
Targeted investment portfolio allocated	90.00%
Pension Plan [Member]
Increase decrease in accrued pension liability	$ 1,375,329	$ 40,601

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Employee Stock Ownership Plan ESOP Longterm Debt Incurred From Repurchasing Participants Shares

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Employee Stock Ownership Plan ESOP Unreleased Shares Are Pledged As Collateral

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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Per share or per unit amount of equity securities issued.

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