Loans and Allowance for Loan Losses - Schedule of Past Due Financing Receivables (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Loans, Total past due loans accruing	$ 3,514	$ 1,671
Loans, Non-accrual loans	7,806	5,236
Loan, Total past due and non-accrual loans	11,320	6,907
Loan, Total loans not past due	$ 505,042	$ 488,340
Percent of gross loans, 30-59 days delinquent and accruing	0.34%	0.24%
Percent of gross loans, 60-89 days delinquent and accruing	0.30%	0.10%
Percent of gross loans, 90 days or more delinquent and accruing	0.04%	0.00%
Percentage of gross loans, Total past due loans accruing	0.68%	0.34%
Percent of gross loans, Non-accrual loans	1.51%	1.06%
Percentage of Total past due and non-accrual loans	2.19%	1.40%
Percentage of Total loans not past due	97.81%	98.60%
Agriculture Loans [Member]
Loans, Total past due loans accruing	$ 1,588	$ 188
Loans, Non-accrual loans	336	482
Loan, Total past due and non-accrual loans	1,924	670
Loan, Total loans not past due	97,469	95,962
Municipal Loans [Member]
Loans, Total past due loans accruing
Loans, Non-accrual loans
Loan, Total past due and non-accrual loans
Loan, Total loans not past due	2,787	2,953
Consumer Loans [Member]
Loans, Total past due loans accruing	88	129
Loans, Non-accrual loans	38	45
Loan, Total past due and non-accrual loans	126	174
Loan, Total loans not past due	24,015	25,254
Commercial Loans [Member]
Loans, Total past due loans accruing	478	418
Loans, Non-accrual loans	1,672	1,528
Loan, Total past due and non-accrual loans	2,150	1,946
Loan, Total loans not past due	92,229	72,343
30-59 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	1,731	1,200
30-59 Days Delinquent and Accruing [Member] \| Agriculture Loans [Member]
Loans, Total past due loans accruing		100
30-59 Days Delinquent and Accruing [Member] \| Municipal Loans [Member]
Loans, Total past due loans accruing
30-59 Days Delinquent and Accruing [Member] \| Commercial Loans [Member]
Loans, Total past due loans accruing		398
60-89 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	1,574	471
60-89 Days Delinquent and Accruing [Member] \| Agriculture Loans [Member]
Loans, Total past due loans accruing	941	88
60-89 Days Delinquent and Accruing [Member] \| Municipal Loans [Member]
Loans, Total past due loans accruing
60-89 Days Delinquent and Accruing [Member] \| Consumer Loans [Member]
Loans, Total past due loans accruing	3	23
60-89 Days Delinquent and Accruing [Member] \| Commercial Loans [Member]
Loans, Total past due loans accruing		20
90 Days or More Delinquent and Accruing [Member]
Loans, Total past due loans accruing	209
One-to-Four Family Residential Real Estate Loans [Member]
Loans, Total past due loans accruing	548	337
Loans, Non-accrual loans	1,197	442
Loan, Total past due and non-accrual loans	1,745	779
Loan, Total loans not past due	133,960	136,116
One-to-Four Family Residential Real Estate Loans [Member] \| 30-59 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	86	131
One-to-Four Family Residential Real Estate Loans [Member] \| 60-89 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	462	206
One-to-Four Family Residential Real Estate Loans [Member] \| 90 Days or More Delinquent and Accruing [Member]
Loans, Total past due loans accruing
Construction and Land Loan [Member]
Loans, Total past due loans accruing	126	134
Loans, Non-accrual loans	1,338	948
Loan, Total past due and non-accrual loans	1,464	1,082
Loan, Total loans not past due	18,586	19,001
Construction and Land Loan [Member] \| 30-59 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing
Construction and Land Loan [Member] \| 60-89 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	126	134
Construction and Land Loan [Member] \| 90 Days or More Delinquent and Accruing [Member]
Loans, Total past due loans accruing
Commercial Real Estate Loans [Member]
Loans, Total past due loans accruing	686	465
Loans, Non-accrual loans	3,225	1,791
Loan, Total past due and non-accrual loans	3,911	2,256
Loan, Total loans not past due	135,996	136,711
Commercial Real Estate Loans [Member] \| 30-59 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	686	465
Commercial Real Estate Loans [Member] \| 60-89 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing
Commercial Real Estate Loans [Member] \| 90 Days or More Delinquent and Accruing [Member]
Loans, Total past due loans accruing
Commercial Loans [Member] \| 30-59 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	436
Commercial Loans [Member] \| 60-89 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	42
Commercial Loans [Member] \| 90 Days or More Delinquent and Accruing [Member]
Loans, Total past due loans accruing
Agriculture Loans [Member] \| 30-59 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	438
Agriculture Loans [Member] \| 90 Days or More Delinquent and Accruing [Member]
Loans, Total past due loans accruing	209
Municipal Loans [Member] \| 30-59 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing
Municipal Loans [Member] \| 90 Days or More Delinquent and Accruing [Member]
Loans, Total past due loans accruing
Consumer Loans [Member] \| 30-59 Days Delinquent and Accruing [Member]
Loans, Total past due loans accruing	85	106
Consumer Loans [Member] \| 90 Days or More Delinquent and Accruing [Member]
Loans, Total past due loans accruing

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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No definition available.

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No definition available.

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

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No definition available.

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No definition available.

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