Loans - Summary of Allowance for Loan Losses and Recorded Investment in Loans by Portfolio Segment and Based on Impairment Method (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Allowance for Loan Losses
Beginning Balance	$ 3,827	$ 3,778
Provision for loan losses	928	556
Loan charge-offs	(844)	(816)
Loan recoveries	146	309
Ending Balance	4,007	3,827
Ending Balance, Individually evaluated for impairment	1,275	1,314
Ending Balance, Collectively evaluated for impairment	2,732	2,513
Loans, Individually evaluated for impairment	7,531	5,329
Loans, Collectively evaluated for impairment	$ 514,524	$ 481,070
Loans, Percent of loans in each category to total loans	100.00%	100.00%
Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Loans, Acquired loans with deteriorated credit quality		$ 823
Home Equity Lines of Credit
Allowance for Loan Losses
Beginning Balance	$ 150	437
Provision for loan losses	164	30
Loan charge-offs	(141)	(333)
Loan recoveries	17	16
Ending Balance	187	150
Ending Balance, Collectively evaluated for impairment	187	150
Loans, Individually evaluated for impairment	200	100
Loans, Collectively evaluated for impairment	$ 35,561	$ 32,869
Loans, Percent of loans in each category to total loans	6.90%	6.80%
Commercial Loans
Allowance for Loan Losses
Beginning Balance	$ 1,250	$ 652
Provision for loan losses	26	631
Loan charge-offs	(487)	(90)
Loan recoveries	40	57
Ending Balance	829	1,250
Ending Balance, Individually evaluated for impairment	456	776
Ending Balance, Collectively evaluated for impairment	373	474
Loans, Individually evaluated for impairment	685	1,443
Loans, Collectively evaluated for impairment	$ 90,119	$ 78,020
Loans, Percent of loans in each category to total loans	17.40%	16.30%
Commercial Loans \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Loans, Acquired loans with deteriorated credit quality		$ 144
Consumer Loans
Allowance for Loan Losses
Beginning Balance	$ 188	491
Provision for loan losses	140	(220)
Loan charge-offs	(187)	(126)
Loan recoveries	58	43
Ending Balance	199	188
Ending Balance, Individually evaluated for impairment	19
Ending Balance, Collectively evaluated for impairment	180	188
Loans, Individually evaluated for impairment	39
Loans, Collectively evaluated for impairment	$ 20,819	$ 19,540
Loans, Percent of loans in each category to total loans	4.00%	4.00%
Consumer Loans \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Loans, Acquired loans with deteriorated credit quality		$ 17
Real Estate Mortgage Loans \| Residential
Allowance for Loan Losses
Beginning Balance	$ 368	304
Provision for loan losses	243	63
Loan charge-offs	(14)
Loan recoveries	5	1
Ending Balance	563	368
Ending Balance, Individually evaluated for impairment	53
Ending Balance, Collectively evaluated for impairment	510	368
Loans, Individually evaluated for impairment	1,201	1,444
Loans, Collectively evaluated for impairment	$ 134,440	$ 132,726
Loans, Percent of loans in each category to total loans	26.00%	27.60%
Real Estate Mortgage Loans \| Residential \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Loans, Acquired loans with deteriorated credit quality		$ 105
Real Estate Mortgage Loans \| Commercial
Allowance for Loan Losses
Beginning Balance	$ 1,302	1,267
Provision for loan losses	219	302
Loan charge-offs	(15)	(267)
Ending Balance	1,506	1,302
Ending Balance, Individually evaluated for impairment	747	493
Ending Balance, Collectively evaluated for impairment	759	809
Loans, Individually evaluated for impairment	5,375	2,242
Loans, Collectively evaluated for impairment	$ 169,167	$ 162,281
Loans, Percent of loans in each category to total loans	33.40%	33.90%
Real Estate Mortgage Loans \| Commercial \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Loans, Acquired loans with deteriorated credit quality		$ 530
Real Estate Mortgage Loans \| Construction and Land Development
Allowance for Loan Losses
Beginning Balance	$ 569	627
Provision for loan losses	136	(250)
Loan recoveries	26	192
Ending Balance	723	569
Ending Balance, Individually evaluated for impairment		45
Ending Balance, Collectively evaluated for impairment	723	524
Loans, Individually evaluated for impairment	31	100
Loans, Collectively evaluated for impairment	$ 64,418	$ 55,634
Loans, Percent of loans in each category to total loans	12.30%	11.40%
Real Estate Mortgage Loans \| Construction and Land Development \| Receivables Acquired with Deteriorated Credit Quality
Allowance for Loan Losses
Loans, Acquired loans with deteriorated credit quality		$ 27

Allowance for loan losses.

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Loans and leases receivable as percentage of aggregate portfolio.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

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Amount of expense related to estimated loss from loan and lease transactions.

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