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, 2018	Dec. 31, 2017
Unpaid Principal Balance	$ 5,191,191	$ 5,265,922
Recorded Investment With No Allowance	3,151,756	2,204,527
Recorded Investment With Allowance	1,642,352	2,691,203
Total Recorded Investment	4,794,108	4,895,730
Related Allowance	454,273	331,779
Year-to-date Average Recorded Investment	10,494,466	10,612,218
Interest Income Received During Impairment	59,744	207,180
Commercial, Financial and Agricultural Loans [Member]
Unpaid Principal Balance	605,565	459,003
Recorded Investment With No Allowance	70,123	208,032
Recorded Investment With Allowance	448,788	250,971
Total Recorded Investment	518,911	459,003
Related Allowance	189,015	44,468
Year-to-date Average Recorded Investment	294,849	190,994
Interest Income Received During Impairment	2,627	10,920
Construction Loans [Member]
Unpaid Principal Balance	424,050	549,599
Recorded Investment With No Allowance	303,250	428,799
Recorded Investment With Allowance	0	0
Total Recorded Investment	303,250	428,799
Related Allowance	0	0
Year-to-date Average Recorded Investment	358,039	299,609
Interest Income Received During Impairment	7,232	24,487
Commercial Mortgage Loans [Member]
Unpaid Principal Balance	1,879,635	1,615,811
Recorded Investment With No Allowance	1,371,860	1,107,654
Recorded Investment With Allowance	339,058	339,440
Total Recorded Investment	1,710,918	1,447,094
Related Allowance	57,021	57,403
Year-to-date Average Recorded Investment	4,468,807	4,130,250
Interest Income Received During Impairment	12,477	54,582
Residential Loans [Member]
Unpaid Principal Balance	2,122,566	2,476,728
Recorded Investment With No Allowance	1,266,383	316,230
Recorded Investment With Allowance	835,271	2,079,823
Total Recorded Investment	2,101,654	2,396,053
Related Allowance	204,979	224,916
Year-to-date Average Recorded Investment	4,636,702	5,277,602
Interest Income Received During Impairment	35,209	108,472
Agricultural Loans [Member]
Unpaid Principal Balance	139,919	142,966
Recorded Investment With No Allowance	139,919	142,966
Recorded Investment With Allowance	0	0
Total Recorded Investment	139,919	142,966
Related Allowance	0	0
Year-to-date Average Recorded Investment	722,595	703,079
Interest Income Received During Impairment	1,755	8,198
Consumer and Other Loans [Member]
Unpaid Principal Balance	19,456	21,815
Recorded Investment With No Allowance	221	846
Recorded Investment With Allowance	19,235	20,969
Total Recorded Investment	19,456	21,815
Related Allowance	3,258	4,992
Year-to-date Average Recorded Investment	13,474	10,684
Interest Income Received During Impairment	$ 444	$ 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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-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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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5278-111524

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