Loans and Allowance for Loan Losses - Schedule of Past Due Financing Receivables (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	1,530	1,355
Loans, Non-accrual loans	5,285	6,041
Loan, Total past due and non-accrual loans	6,815	7,396
Loan, Total loans not past due	$ 460,322	$ 431,840
Percent of gross loans, 30-59 days delinquent and accruing	0.07%	0.05%
Percent of gross loans, 60-89 days delinquent and accruing	0.26%	0.26%
Percent of gross loans, 90 days or more delinquent and accruing	0.00%	0.00%
Percentage of gross loans, Total past due loans accruing	0.33%	0.31%
Percent of gross loans, Non-accrual loans	1.13%	1.37%
Percentage of Total past due and non-accrual loans	1.46%	1.68%
Percentage of Total loans not past due	98.54%	98.32%
Commercial Loan [Member]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	759	397
Loans, Non-accrual loans	2,032	2,002
Loan, Total past due and non-accrual loans	2,791	2,399
Loan, Total loans not past due	63,740	52,192
Agriculture Loan [Member]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	303
Loans, Non-accrual loans	384	833
Loan, Total past due and non-accrual loans	687	833
Loan, Total loans not past due	87,214	82,175
Municipal Loan [Member]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing
Loans, Non-accrual loans
Loan, Total past due and non-accrual loans
Loan, Total loans not past due	3,172	3,396
Consumer Loan [Member]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	79	309
Loans, Non-accrual loans	46	34
Loan, Total past due and non-accrual loans	125	343
Loan, Total loans not past due	22,742	21,703
30-59 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due	311	228
30-59 Days Delinquent and Accruing [Member] \| Commercial Loan [Member]
Financing Receivable, Recorded Investment, Past Due	48
30-59 Days Delinquent and Accruing [Member] \| Agriculture Loan [Member]
Financing Receivable, Recorded Investment, Past Due	127
30-59 Days Delinquent and Accruing [Member] \| Municipal Loan [Member]
Financing Receivable, Recorded Investment, Past Due
30-59 Days Delinquent and Accruing [Member] \| Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due	36	105
60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due	1,219	1,127
60-89 Days Delinquent and Accruing [Member] \| Commercial Loan [Member]
Financing Receivable, Recorded Investment, Past Due	711	397
60-89 Days Delinquent and Accruing [Member] \| Agriculture Loan [Member]
Financing Receivable, Recorded Investment, Past Due	176
60-89 Days Delinquent and Accruing [Member] \| Municipal Loan [Member]
Financing Receivable, Recorded Investment, Past Due
60-89 Days Delinquent and Accruing [Member] \| Consumer Loan [Member]
Financing Receivable, Recorded Investment, Past Due	43	204
One-To-Four Family Residential Real Estate Loan [Member]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	389	414
Loans, Non-accrual loans	463	552
Loan, Total past due and non-accrual loans	852	966
Loan, Total loans not past due	137,415	135,249
One-To-Four Family Residential Real Estate Loan [Member] \| 30-59 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due	100	101
One-To-Four Family Residential Real Estate Loan [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due	289	313
Construction and Land Loan [Member]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing		4
Loans, Non-accrual loans	567	779
Loan, Total past due and non-accrual loans	567	783
Loan, Total loans not past due	25,886	18,573
Construction and Land Loan [Member] \| 30-59 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due
Construction and Land Loan [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due		4
Commercial Real Estate Loan [Member]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing		231
Loans, Non-accrual loans	1,793	1,841
Loan, Total past due and non-accrual loans	1,793	2,072
Loan, Total loans not past due	120,153	118,552
Commercial Real Estate Loan [Member] \| 30-59 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due		22
Commercial Real Estate Loan [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due		$ 209

Recorded investment in Financing receivables that are 30 days or more past due and accruing, total.

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Percentage amount of Recorded investment in financing receivables that are 30 days or more past due and accruing, total.

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Percentage amount of financing receivables that are less than 60 days past due but more than 29 days past due.

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Percentage amount of financing receivables that are less than 90 days past due but more than 59 days past due.

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

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No definition available.

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Percentage of financing receivables that are current.

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

+ References

No definition available.

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Recorded investment that are past due including non accrual status.

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Percentage of recorded investment that are past due including non accrual status.

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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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Financing receivables that are current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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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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Recorded Investment in financing receivables that are past due at the balance sheet date.

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