Loans and Allowance for Loan Losses - Schedule of Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Allowance for Loan Losses [Roll Forward]
Beginning balance			$ 5,176	$ 5,094	$ 5,094
Charge-offs			(107)	(505)	(783)
Recoveries			85	77	358
Provision (recovery)	$ 205	$ 12	255	312	507
Ending balance	5,409	4,978	5,409	4,978	5,176
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	383		383		403
Ending balances collectively evaluated for impairment	5,026		5,026		4,773
Loans receivable, individually evaluated for impairment	5,637		5,637		7,666
Loans receivable, collectively evaluated for impairment	538,365		538,365		541,698
Total financing receivables	544,002		544,002		549,364
Commercial and Industrial [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance			483	518	518
Charge-offs			(74)	(88)	(106)
Recoveries			1	14	35
Provision (recovery)			162	(15)	36
Ending balance	572	429	572	429	483
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	158		158		176
Ending balances collectively evaluated for impairment	414		414		307
Loans receivable, individually evaluated for impairment	575		575		522
Loans receivable, collectively evaluated for impairment	28,530		28,530		26,199
Total financing receivables	29,105		29,105		26,721
Commercial Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance			1,738	1,609	1,609
Charge-offs			0	0	(47)
Recoveries			75	10	70
Provision (recovery)			(34)	217	106
Ending balance	1,779	1,836	1,779	1,836	1,738
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	139		139		159
Ending balances collectively evaluated for impairment	1,640		1,640		1,579
Loans receivable, individually evaluated for impairment	2,895		2,895		3,191
Loans receivable, collectively evaluated for impairment	178,182		178,182		184,606
Total financing receivables	181,077		181,077		187,797
Construction and Land [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance			635	879	879
Charge-offs			0	(312)	(312)
Recoveries			0	0	0
Provision (recovery)			15	(115)	68
Ending balance	650	452	650	452	635
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	650		650		635
Loans receivable, individually evaluated for impairment	726		726		2,679
Loans receivable, collectively evaluated for impairment	64,608		64,608		68,730
Total financing receivables	65,334		65,334		71,409
Consumer [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance			145	105	105
Charge-offs			(23)	(10)	(14)
Recoveries			9	4	4
Provision (recovery)			10	10	50
Ending balance	141	109	141	109	145
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	141		141		145
Loans receivable, individually evaluated for impairment	0		0		0
Loans receivable, collectively evaluated for impairment	5,372		5,372		5,562
Total financing receivables	5,372		5,372		5,562
Student [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance			68	72	72
Charge-offs			(10)	(15)	(24)
Recoveries			0	0	0
Provision (recovery)			9	21	20
Ending balance	67	78	67	78	68
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	67		67		68
Loans receivable, individually evaluated for impairment	0		0		0
Loans receivable, collectively evaluated for impairment	8,583		8,583		9,158
Total financing receivables	8,583		8,583		9,158
Residential Real Estate [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance			1,311	1,174	1,174
Charge-offs			0	0	(200)
Recoveries			0	48	248
Provision (recovery)			137	77	89
Ending balance	1,448	1,299	1,448	1,299	1,311
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	1,448		1,448		1,311
Loans receivable, individually evaluated for impairment	690		690		707
Loans receivable, collectively evaluated for impairment	213,385		213,385		205,238
Total financing receivables	214,075		214,075		205,945
Home Equity Lines of Credit [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance			446	387	387
Charge-offs			0	(80)	(80)
Recoveries			0	1	1
Provision (recovery)			(44)	117	138
Ending balance	402	425	402	425	446
Additional Information on Allowance for Loan Losses and Recorded Investment in Loans Receivable [Abstract]
Ending balances individually evaluated for impairment	86		86		68
Ending balances collectively evaluated for impairment	316		316		378
Loans receivable, individually evaluated for impairment	751		751		567
Loans receivable, collectively evaluated for impairment	39,705		39,705		42,205
Total financing receivables	40,456		40,456		42,772
Unallocated [Member]
Allowance for Loan Losses [Roll Forward]
Beginning balance			350	350	350
Charge-offs			0	0	0
Recoveries			0	0	0
Provision (recovery)			0	0	0
Ending balance	350	$ 350	350	$ 350	350
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		$ 350

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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