Loans and Allowance for Loan Losses - Schedule of Past Due Financing Receivables (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	2,913	758
Loans, Non-accrual loans	5,489	2,746
Loan, Total past due and non-accrual loans	8,402	3,504
Loan, Total loans not past due	$ 425,652	$ 422,265
Percent of gross loans, 30-59 days delinquent and accruing	0.51%	0.09%
Percent of gross loans, 60-89 days delinquent and accruing	0.16%	0.09%
Percent of gross loans, 90 days or more delinquent and accruing	0.00%	0.00%
Percentage of gross loans, Total past due loans accruing	0.67%	0.18%
Percent of gross loans, Non-accrual loans	1.26%	0.64%
Percentage of Total past due and non-accrual loans	1.94%	0.82%
Percentage of Total loans not past due	98.06%	99.18%
30-59Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	$ 2,219	$ 215
60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	694	396
Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	50	18
Loans, Non-accrual loans		342
Loan, Total past due and non-accrual loans	1,629	360
Loan, Total loans not past due	49,315	54,146
Commercial [Member] \| 30-59Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	50
Commercial [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due		5
Agriculture [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	678	55
Loans, Non-accrual loans	883	838
Loan, Total past due and non-accrual loans	1,561	893
Loan, Total loans not past due	82,540	77,431
Agriculture [Member] \| 30-59Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	588
Agriculture [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	90
Municipal [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
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	3,479	3,884
Municipal [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due
Municipal [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due
Consumer Loan [Member] \| 30-59Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	122	79
Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	127	82
Loans, Non-accrual loans	44	72
Loan, Total past due and non-accrual loans	171	154
Loan, Total loans not past due	21,814	20,117
Consumer [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	5	3
One-To-Four Family Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	1,416	603
Loans, Non-accrual loans	333	595
Loan, Total past due and non-accrual loans	1,749	1,198
Loan, Total loans not past due	135,080	135,648
One-To-Four Family Residential Real Estate [Member] \| 30-59Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	1,163
One-To-Four Family Residential Real Estate [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	253	388
Construction and Land [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	432
Loans, Non-accrual loans	786	599
Loan, Total past due and non-accrual loans	1,218	599
Loan, Total loans not past due	14,680	13,139
Construction and Land [Member] \| 30-59Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	86
Construction and Land [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	346
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans, 90 days or more delinquent and accruing
Loans, Total past due loans accruing	210
Loans, Non-accrual loans	1,864	300
Loan, Total past due and non-accrual loans	2,074	300
Loan, Total loans not past due	118,744	117,900
Commercial Real Estate [Member] \| 30-59Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	210
Commercial Real Estate [Member] \| 60-89 Days Delinquent and Accruing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due

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

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- Definition

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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- Definition

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

+ References

No definition available.

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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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- Definition

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

+ References

No definition available.

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- Definition

Percentage of financing receivables that are current.

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- Definition

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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- Definition

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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No definition available.

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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://www.xbrl.org/2003/role/presentationRef
-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

Financing receivables that are current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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