Loans, Impaired Financing Receivable Loan Type (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Summary of certain impaired loan information [Abstract]
Non-accrual loans	$ 12,049	$ 10,768
Accruing loans past due 90 days or more	885	606
TDR loans	9,187	$ 9,308
Increase accruing loans past due 90 days or more	$ 280
Number of accruing loans past due 90 days or more	15	8
Average 90 days or more past due loan balance	$ 60	$ 80
Agricultural [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	1,356	1,192
Accruing loans past due 90 days or more	20	48
TDR loans	425	404
Commercial and financial [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	1,295	679
Accruing loans past due 90 days or more	176	65
TDR loans	1,859	1,934
Real Estate: Construction, 1 to 4 family residential [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	0	0
Accruing loans past due 90 days or more	0	0
TDR loans	0	0
Real Estate: Construction, land development and commercial [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	0	0
Accruing loans past due 90 days or more	0	0
TDR loans	319	320
Real Estate: Mortgage, farmland [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	1,288	1,369
Accruing loans past due 90 days or more	161	0
TDR loans	2,681	2,712
Real Estate: Mortgage, 1 to 4 family first liens [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	6,489	6,558
Accruing loans past due 90 days or more	528	354
TDR loans	1,615	1,626
Real Estate: Mortgage, 1 to 4 family junior liens [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	240	94
Accruing loans past due 90 days or more	0	139
TDR loans	0	0
Real Estate: Mortgage, multi-family [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	95	97
Accruing loans past due 90 days or more	0	0
TDR loans	1,709	1,719
Real Estate: Mortgage, commercial [Member]
Summary of certain impaired loan information [Abstract]
Non-accrual loans	1,286	779
Accruing loans past due 90 days or more	0	0
TDR loans	579	593
Loans to individuals [Member]
Summary of certain impaired loan information [Abstract]
Accruing loans past due 90 days or more	0	0
Troubled Debt Restructuring [Member]
Summary of certain impaired loan information [Abstract]
TDR Loans included within nonaccrual loans	$ 4,990	$ 4,340

Represents average past due financing receivable.

No definition available.

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- Definition

Recorded investment in financing receivables that are troubled debt restructuring loans.

+ References

No definition available.

+ Details

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- Definition

Increase (Decrease) Impaired Financing Receivable Accruing Interest Unpaid Principal Balance

+ References

No definition available.

+ Details

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- Definition

Number of accruing loans past due 90 days or more

+ References

No definition available.

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- Definition

Summary of certain impaired loan information [Abstract]

+ References

No definition available.

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- Definition

Recorded investment in financing receivables that have undergone troubled debt restructuring and are on nonaccrual status as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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