Loans and Allowance for Loan Losses - Schedule of Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for Loan Losses [Roll Forward]
Beginning balance	$ 5,094	$ 4,525	$ 4,193
Charge-offs	(783)	(691)	(724)
Recoveries	358	740	1,564
Provision (recovery)	507	520	(508)
Ending balance	5,176	5,094	4,525
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	403	912	880
Ending balances collectively evaluated for impairment	4,773	4,182	3,645
Loans receivable, individually evaluated for impairment	7,666	10,862	8,484
Loans receivable, collectively evaluated for impairment	541,698	491,937	454,649
Total financing receivables	549,364	502,799	463,133
Commercial and Industrial [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	518	561	526
Charge-offs	(106)	(19)	(226)
Recoveries	35	154	1,527
Provision (recovery)	36	(178)	(1,266)
Ending balance	483	518	561
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	176	247	100
Ending balances collectively evaluated for impairment	307	271	461
Loans receivable, individually evaluated for impairment	522	758	227
Loans receivable, collectively evaluated for impairment	26,199	23,655	25,508
Total financing receivables	26,721	24,413	25,735
Commercial Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	1,609	1,569	1,162
Charge-offs	(47)	(476)	(380)
Recoveries	70	575	24
Provision (recovery)	106	(59)	763
Ending balance	1,738	1,609	1,569
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	159	257	398
Ending balances collectively evaluated for impairment	1,579	1,352	1,171
Loans receivable, individually evaluated for impairment	3,191	3,631	3,273
Loans receivable, collectively evaluated for impairment	184,606	173,196	161,998
Total financing receivables	187,797	176,827	165,271
Construction and Land [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	879	661	924
Charge-offs	(312)	0	0
Recoveries	0	0	0
Provision (recovery)	68	218	(263)
Ending balance	635	879	661
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	357	309
Ending balances collectively evaluated for impairment	635	522	352
Loans receivable, individually evaluated for impairment	2,679	5,234	3,504
Loans receivable, collectively evaluated for impairment	68,730	48,928	46,273
Total financing receivables	71,409	54,162	49,777
Consumer [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	105	21	13
Charge-offs	(14)	(114)	(46)
Recoveries	4	2	10
Provision (recovery)	50	196	44
Ending balance	145	105	21
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	0
Ending balances collectively evaluated for impairment	145	105	21
Loans receivable, individually evaluated for impairment	0	0	0
Loans receivable, collectively evaluated for impairment	5,562	5,068	3,100
Total financing receivables	5,562	5,068	3,100
Student [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	72	76	117
Charge-offs	(24)	(31)	(36)
Recoveries	0	0	0
Provision (recovery)	20	27	(5)
Ending balance	68	72	76
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	0
Ending balances collectively evaluated for impairment	68	72	76
Loans receivable, individually evaluated for impairment	0	0	0
Loans receivable, collectively evaluated for impairment	9,158	10,677	13,006
Total financing receivables	9,158	10,677	13,006
Residential Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	1,174	943	886
Charge-offs	(200)	(51)	(36)
Recoveries	248	6	0
Provision (recovery)	89	276	93
Ending balance	1,311	1,174	943
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	73
Ending balances collectively evaluated for impairment	1,311	1,174	870
Loans receivable, individually evaluated for impairment	707	581	1,410
Loans receivable, collectively evaluated for impairment	205,238	186,523	160,973
Total financing receivables	205,945	187,104	162,383
Home Equity Lines of Credit [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	387	307	356
Charge-offs	(80)	0	0
Recoveries	1	3	3
Provision (recovery)	138	77	(52)
Ending balance	446	387	307
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	68	51	0
Ending balances collectively evaluated for impairment	378	336	307
Loans receivable, individually evaluated for impairment	567	658	70
Loans receivable, collectively evaluated for impairment	42,205	43,890	43,791
Total financing receivables	42,772	44,548	43,861
Unallocated [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance	350	387	209
Charge-offs	0	0	0
Recoveries	0	0	0
Provision (recovery)	0	(37)	178
Ending balance	350	350	387
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	0	0	0
Ending balances collectively evaluated for impairment	350	350	387
Loans receivable, individually evaluated for impairment	0	0	0
Loans receivable, collectively evaluated for impairment	0	0	0
Total financing receivables	$ 0	$ 0	$ 0

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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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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

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