Employee Benefits and Retirement Plans (Details Narrative) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Increase decrease in accrued pension liability	$ 721,735	$ 716,622	$ 775,423
Changes to other comprehensive income (loss) on pre-tax basis	(32,075)	62,698
Increased in fair value of plan assets	$ 993,057
Targeted investment portfolio allocated	45.00%
Investments	$ 300,000,000
Estimated amortization amounts, net loss	580,843
Expected contribute from employer	460,000	480,000	550,000
Expense incurred	$ (412,047)	129,086	472,947
Stock options exercise period	10 years
Pension Plan 2019 [Member]
Expected contribute from employer	$ 400,000
Southwest Georgia Bank 401(K) Plan [Member]
Employee contributions	219,006	204,565	186,253
Employee Stock Ownership Plan [Member]
Expected contribute from employer	$ 475,000	425,000	400,000
ESOP holds Corporation's outstanding common stock	252,248
Number of shares are allocated to participants	223,203
Unreleased shares are pledged as collateral	29,045
Long-term debt incurred from repurchasing participants' shares	$ 640,000
Directors and Executive Officers Stock Purchase Plan [Member]
Employee contributions	900
Expense incurred	$ 248,800	$ 265,900	$ 290,573
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	5,726	5,286	6,955
Shares issued at an average price per share	$ 22.63	$ 21.18	$ 15.92
2013 Omnibus Incentive Plan [Member]
Stock options exercise period	5 years
Common stock authorized for issuance	125,000
Number of restricted stock awards shares granted during the period	13,316
Restricted stock awards vested	854
Incentive Plan [Member]
Number of restricted stock awards shares granted during the period		4,271
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	$ 40,601	$ 503,167

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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 included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

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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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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Per share or per unit amount of equity securities issued.

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