Loans and Allowance for Loan Losses - Schedule of Impaired Loans Segregated by Class of Loans (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Unpaid Principal Balance	$ 5,771,251	$ 5,265,922
Recorded Investment With No Allowance	3,534,026	2,204,527
Recorded Investment With Allowance	1,725,494	2,691,203
Total Recorded Investment	5,259,520	4,895,730
Related Allowance	563,476	331,779
Year-to-date Average Recorded Investment	4,434,451	3,789,822
Interest Income Received During Impairment	125,729	207,180
Commercial, Financial and Agricultural Loans [Member]
Unpaid Principal Balance	1,235,050	459,003
Recorded Investment With No Allowance	427,276	208,032
Recorded Investment With Allowance	606,472	250,971
Total Recorded Investment	1,033,748	459,003
Related Allowance	306,543	44,468
Year-to-date Average Recorded Investment	509,358	169,930
Interest Income Received During Impairment	12,446	10,920
Construction Loans [Member]
Unpaid Principal Balance	420,625	549,599
Recorded Investment With No Allowance	299,825	428,799
Recorded Investment With Allowance	0	0
Total Recorded Investment	299,825	428,799
Related Allowance	0	0
Year-to-date Average Recorded Investment	299,825	162,698
Interest Income Received During Impairment	12,896	24,487
Commercial Mortgage Loans [Member]
Unpaid Principal Balance	2,003,797	1,615,811
Recorded Investment With No Allowance	1,497,705	1,107,654
Recorded Investment With Allowance	337,375	339,440
Total Recorded Investment	1,835,080	1,447,094
Related Allowance	55,338	57,403
Year-to-date Average Recorded Investment	1,573,756	1,071,663
Interest Income Received During Impairment	24,533	54,582
Residential Loans [Member]
Unpaid Principal Balance	1,956,522	2,476,728
Recorded Investment With No Allowance	1,172,306	316,230
Recorded Investment With Allowance	763,304	2,079,823
Total Recorded Investment	1,935,610	2,396,053
Related Allowance	199,229	224,916
Year-to-date Average Recorded Investment	1,896,255	2,233,562
Interest Income Received During Impairment	71,510	108,472
Agricultural Loans [Member]
Unpaid Principal Balance	136,883	142,966
Recorded Investment With No Allowance	136,883	142,966
Recorded Investment With Allowance	0	0
Total Recorded Investment	136,883	142,966
Related Allowance	0	0
Year-to-date Average Recorded Investment	136,883	142,966
Interest Income Received During Impairment	3,523	8,198
Consumer and Other Loans [Member]
Unpaid Principal Balance	18,374	21,815
Recorded Investment With No Allowance	31	846
Recorded Investment With Allowance	18,343	20,969
Total Recorded Investment	18,374	21,815
Related Allowance	2,366	4,992
Year-to-date Average Recorded Investment	18,374	9,003
Interest Income Received During Impairment	$ 821	$ 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
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