Loans and Allowance for Loan Losses - Schedule of Impaired Loans Segregated by Class of Loans (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Unpaid Principal Balance	$ 5,874,923	$ 5,265,922
Recorded Investment With No Allowance	2,730,106	2,204,527
Recorded Investment With Allowance	2,495,131	2,691,203
Total Recorded Investment	5,225,237	4,895,730
Related Allowance	628,452	331,779
Year-to-date Average Recorded Investment	3,803,239	3,789,822
Interest Income Received During Impairment	193,104	207,180
Commercial, Financial and Agricultural Loans [Member]
Unpaid Principal Balance	1,263,609	459,003
Recorded Investment With No Allowance	291,049	208,032
Recorded Investment With Allowance	640,388	250,971
Total Recorded Investment	931,437	459,003
Related Allowance	319,392	44,468
Year-to-date Average Recorded Investment	283,622	169,930
Interest Income Received During Impairment	31,832	10,920
Construction Loans [Member]
Unpaid Principal Balance	413,803	549,599
Recorded Investment With No Allowance	293,003	428,799
Recorded Investment With Allowance	0	0
Total Recorded Investment	293,003	428,799
Related Allowance	0	0
Year-to-date Average Recorded Investment	254,788	162,698
Interest Income Received During Impairment	17,823	24,487
Commercial Mortgage Loans [Member]
Unpaid Principal Balance	1,791,395	1,615,811
Recorded Investment With No Allowance	1,279,924	1,107,654
Recorded Investment With Allowance	335,669	339,440
Total Recorded Investment	1,615,593	1,447,094
Related Allowance	53,632	57,403
Year-to-date Average Recorded Investment	1,348,557	1,071,663
Interest Income Received During Impairment	37,349	54,582
Residential Loans [Member]
Unpaid Principal Balance	2,046,205	2,476,728
Recorded Investment With No Allowance	520,694	316,230
Recorded Investment With Allowance	1,504,599	2,079,823
Total Recorded Investment	2,025,293	2,396,053
Related Allowance	253,824	224,916
Year-to-date Average Recorded Investment	1,888,312	2,233,562
Interest Income Received During Impairment	100,152	108,472
Agricultural Loans [Member]
Unpaid Principal Balance	345,405	142,966
Recorded Investment With No Allowance	345,405	142,966
Recorded Investment With Allowance	0	0
Total Recorded Investment	345,405	142,966
Related Allowance	0	0
Year-to-date Average Recorded Investment	13,454	142,966
Interest Income Received During Impairment	5,260	8,198
Consumer and Other Loans [Member]
Unpaid Principal Balance	14,506	21,815
Recorded Investment With No Allowance	31	846
Recorded Investment With Allowance	14,475	20,969
Total Recorded Investment	14,506	21,815
Related Allowance	1,604	4,992
Year-to-date Average Recorded Investment	14,506	9,003
Interest Income Received During Impairment	$ 688	$ 521

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=84173941&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=84173941&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
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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