Loans Receivable and Allowance for Loan Losses, Changes in Allowance for Loan Losses and Recorded Investment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Allowance for Loan losses [Roll Forward]
Beginning Balance	$ 8,044	$ 8,055
Charge-offs		(336)
Recoveries	41	450
Net (charge-offs) recoveries	41	114
Ending Balance	8,085	8,169
Ending balance - individually evaluated for impairment			$ 1,030	$ 1,533	$ 1,653
Ending balance - collectively evaluated for impairment			7,055	6,511	6,516
Ending balance	8,044	8,055	8,085	8,044	8,169
Ending loan balance - individually evaluated for impairment			16,232	17,226	22,878
Ending loan balance - collectively evaluated for impairment			657,988	665,123	647,034
Ending loan balance			674,220	682,349	669,912
Residential Mortgage [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	2,224	3,099
Charge-offs		(323)
Recoveries	5	221
Net (charge-offs) recoveries	5	(102)
Provision for (reversal of) loan losses	343	304
Ending Balance	2,572	3,301
Ending balance - individually evaluated for impairment			905	927	1,285
Ending balance - collectively evaluated for impairment			1,667	1,297	2,016
Ending balance	2,224	3,099	2,572	2,224	3,301
Ending loan balance - individually evaluated for impairment			12,259	12,579	17,439
Ending loan balance - collectively evaluated for impairment			257,184	262,180	267,584
Ending loan balance			269,443	274,759	285,023
Commercial [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	2,736	527
Provision for (reversal of) loan losses	(996)	(13)
Ending Balance	1,740	514
Ending balance - individually evaluated for impairment				430
Ending balance - collectively evaluated for impairment			1,740	2,306	514
Ending balance	2,736	527	1,740	2,736	514
Ending loan balance - individually evaluated for impairment				430	296
Ending loan balance - collectively evaluated for impairment			44,725	35,454	38,719
Ending loan balance			44,725	35,884	39,015
Commercial Real Estate [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	457	2,805
Recoveries	34	211
Net (charge-offs) recoveries	34	211
Provision for (reversal of) loan losses	221	(21)
Ending Balance	712	2,995
Ending balance - individually evaluated for impairment			91	142	318
Ending balance - collectively evaluated for impairment			621	315	2,677
Ending balance	457	2,805	712	457	2,995
Ending loan balance - individually evaluated for impairment			1,934	1,992	2,820
Ending loan balance - collectively evaluated for impairment			235,325	240,701	227,516
Ending loan balance			237,259	242,693	230,336
ADC [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	2,239	1,236
Charge-offs		(13)
Net (charge-offs) recoveries		(13)
Provision for (reversal of) loan losses	340	(163)
Ending Balance	2,579	1,060
Ending balance - individually evaluated for impairment			32	32	47
Ending balance - collectively evaluated for impairment			2,547	2,207	1,013
Ending balance	2,239	1,236	2,579	2,239	1,060
Ending loan balance - individually evaluated for impairment			1,106	1,278	981
Ending loan balance - collectively evaluated for impairment			107,827	113,262	99,654
Ending loan balance			108,933	114,540	100,635
Home Equity/2nds [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	222	386
Recoveries	2	18
Net (charge-offs) recoveries	2	18
Provision for (reversal of) loan losses	18	(107)
Ending Balance	242	297
Ending balance - individually evaluated for impairment			2	2	2
Ending balance - collectively evaluated for impairment			240	220	295
Ending balance	222	386	242	222	297
Ending loan balance - individually evaluated for impairment			859	871	1,260
Ending loan balance - collectively evaluated for impairment			11,855	12,515	12,593
Ending loan balance			12,714	13,386	13,853
Consumer [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	1	2
Ending Balance	1	2
Ending balance - individually evaluated for impairment					1
Ending balance - collectively evaluated for impairment			1	1	1
Ending balance	1	$ 2	1	1	2
Ending loan balance - individually evaluated for impairment			74	76	82
Ending loan balance - collectively evaluated for impairment			1,072	1,011	968
Ending loan balance			1,146	1,087	$ 1,050
Unallocated
Allowance for Loan losses [Roll Forward]
Beginning Balance	165
Provision for (reversal of) loan losses	74
Ending Balance	239
Ending balance - collectively evaluated for impairment			239	165
Ending balance	$ 165		$ 239	$ 165

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Amount, after recoveries, of loans and leases that have been written-off.

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

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- Definition

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 after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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

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