Loans Receivable and Allowance for Loan Losses, Changes in Allowance for Loan Losses and Recorded Investment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Allowance for Loan losses [Roll Forward]
Beginning Balance	$ 8,257	$ 7,718	$ 8,055	$ 8,969
Charge-offs	(154)		(527)	(805)
Recoveries	253	218	828	422
Net (charge-offs) recoveries	99	218	301	(383)
Provision for (reversal of) loan losses	(300)		(300)	(650)
Ending Balance	8,056	7,936	8,056	7,936
Ending balance - individually evaluated for impairment					$ 2,159	$ 1,413	$ 1,782
Ending balance - collectively evaluated for impairment					5,897	6,642	6,154
Ending balance	8,257	7,718	8,055	8,969	8,056	8,055	7,936
Ending loan balance - individually evaluated for impairment					19,523	22,211	24,888
Ending loan balance - collectively evaluated for impairment					670,189	645,940	626,076
Ending loan balance					689,712	668,151	650,964
Residential Mortgage [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	2,962	3,403	3,099	3,833
Charge-offs	(148)		(508)	(707)
Recoveries	3	156	225	295
Net (charge-offs) recoveries	(145)	156	(283)	(412)
Provision for (reversal of) loan losses	204	(137)	205	1
Ending Balance	3,021	3,422	3,021	3,422
Ending balance - individually evaluated for impairment					1,090	1,181	1,544
Ending balance - collectively evaluated for impairment					1,931	1,918	1,878
Ending balance	2,962	3,403	3,099	3,833	3,021	3,099	3,422
Ending loan balance - individually evaluated for impairment					15,038	18,219	20,379
Ending loan balance - collectively evaluated for impairment					270,432	267,600	268,790
Ending loan balance					285,470	285,819	289,169
Commercial [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	414	389	527	478
Provision for (reversal of) loan losses	219	53	106	(36)
Ending Balance	633	442	633	442
Ending balance - collectively evaluated for impairment					633	527	442
Ending balance	414	389	527	478	633	527	442
Ending loan balance - collectively evaluated for impairment					43,180	37,356	37,485
Ending loan balance					43,180	37,356	37,485
Commercial Real Estate [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	2,591	2,571	2,805	2,535
Recoveries	31	40	364	100
Net (charge-offs) recoveries	31	40	364	100
Provision for (reversal of) loan losses	10	(44)	(537)	(68)
Ending Balance	2,632	2,567	2,632	2,567
Ending balance - individually evaluated for impairment					166	182	186
Ending balance - collectively evaluated for impairment					2,466	2,623	2,381
Ending balance	2,591	2,571	2,805	2,535	2,632	2,805	2,567
Ending loan balance - individually evaluated for impairment					2,053	2,917	3,419
Ending loan balance - collectively evaluated for impairment					232,777	232,212	219,748
Ending loan balance					234,830	235,129	223,167
ADC [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	2,060	984	1,236	1,390
Charge-offs	(6)		(19)
Net (charge-offs) recoveries	(6)		(19)
Provision for (reversal of) loan losses	(494)	158	343	(248)
Ending Balance	1,560	1,142	1,560	1,142
Ending balance - individually evaluated for impairment					900	48	50
Ending balance - collectively evaluated for impairment					660	1,188	1,092
Ending balance	2,060	984	1,236	1,390	1,560	1,236	1,142
Ending loan balance - individually evaluated for impairment					1,582	991	1,003
Ending loan balance - collectively evaluated for impairment					111,412	92,069	83,161
Ending loan balance					112,994	93,060	84,164
Home Equity/2nds [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	229	367	386	728
Charge-offs				(98)
Recoveries	219	22	239	27
Net (charge-offs) recoveries	219	22	239	(71)
Provision for (reversal of) loan losses	(267)	(28)	(444)	(296)
Ending Balance	181	361	181	361
Ending balance - individually evaluated for impairment					2
Ending balance - collectively evaluated for impairment					179	386	361
Ending balance	229	367	386	728	181	386	361
Ending loan balance - individually evaluated for impairment					772
Ending loan balance - collectively evaluated for impairment					11,401	15,703	15,861
Ending loan balance					12,173	15,703	15,861
Consumer [Member]
Allowance for Loan losses [Roll Forward]
Beginning Balance	1	4	2	5
Provision for (reversal of) loan losses		(2)	(1)	(3)
Ending Balance	1	2	1	2
Ending balance - individually evaluated for impairment					1	2	2
Ending balance	1	$ 4	2	$ 5	1	2	2
Ending loan balance - individually evaluated for impairment					78	84	87
Ending loan balance - collectively evaluated for impairment					987	1,000	1,031
Ending loan balance					1,065	$ 1,084	$ 1,118
Unallocated
Allowance for Loan losses [Roll Forward]
Provision for (reversal of) loan losses	28		28
Ending Balance	28		28
Ending balance - collectively evaluated for impairment					28
Ending balance	$ 28		$ 28		$ 28

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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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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