Loans and Allowance for Loan Losses - Schedule of Impaired Loans Segregated by Class of Loans (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Unpaid Principal Balance	$ 4,921,273	$ 4,187,966
Recorded Investment With No Allowance	1,026,038	2,686,743
Recorded Investment With Allowance	3,306,371	1,669,638
Total Recorded Investment	4,332,409	4,356,381
Related Allowance	827,717	518,230
Year-to-date Average Recorded Investment	3,163,895	3,817,174
Interest Income Received During Impairment	52,504	257,334
Commercial, Financial and Agricultural Loans [Member]
Unpaid Principal Balance	1,420,052	184,899
Recorded Investment With No Allowance	78,507	87,525
Recorded Investment With Allowance	1,254,891	568,816
Total Recorded Investment	1,333,398	656,341
Related Allowance	562,925	276,392
Year-to-date Average Recorded Investment	461,763	370,038
Interest Income Received During Impairment	8,225	52,411
Construction Loans [Member]
Unpaid Principal Balance	393,898	402,234
Recorded Investment With No Allowance	273,098	281,434
Recorded Investment With Allowance	0	0
Total Recorded Investment	273,098	281,434
Related Allowance	0	0
Year-to-date Average Recorded Investment	273,098	281,434
Interest Income Received During Impairment	5,253	25,364
Commercial Mortgage Loans [Member]
Unpaid Principal Balance	1,661,727	1,787,305
Recorded Investment With No Allowance	346,979	1,277,611
Recorded Investment With Allowance	954,250	333,892
Total Recorded Investment	1,301,229	1,611,503
Related Allowance	38,678	51,854
Year-to-date Average Recorded Investment	1,097,539	1,544,299
Interest Income Received During Impairment	9,701	45,403
Residential Loans [Member]
Unpaid Principal Balance	1,432,181	1,801,002
Recorded Investment With No Allowance	327,454	1,027,647
Recorded Investment With Allowance	1,083,815	752,443
Total Recorded Investment	1,411,269	1,780,090
Related Allowance	225,215	188,368
Year-to-date Average Recorded Investment	1,318,080	1,594,390
Interest Income Received During Impairment	28,979	127,806
Agricultural Loans [Member]
Unpaid Principal Balance	0	12,526
Recorded Investment With No Allowance	0	12,526
Recorded Investment With Allowance	0	0
Total Recorded Investment	0	12,526
Related Allowance	0	0
Year-to-date Average Recorded Investment	0	12,526
Interest Income Received During Impairment	0	5,530
Consumer and Other Loans [Member]
Unpaid Principal Balance	13,415	0
Recorded Investment With No Allowance	0	0
Recorded Investment With Allowance	13,415	14,487
Total Recorded Investment	13,415	14,487
Related Allowance	899	1,616
Year-to-date Average Recorded Investment	13,415	14,487
Interest Income Received During Impairment	$ 346	$ 820

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953550-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Paragraph 19
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