Allowance for Credit Losses (Allowance for Credit Losses and Recorded Investments In Loans Receivables) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	$ 6,672	$ 6,188	$ 6,675	$ 5,843	$ 5,843
Charge-offs	(152)	(38)	(493)	(472)
Recoveries	8	309	46	338
Provisions	325	100	625	850
Ending balance	6,853	6,559	6,853	6,559	6,675
Ending balance: individually evaluated for impairment	307		307		285
Ending balance: collectively evaluated for impairment	6,546		6,546		6,390
Ending balance: Loans receivables	923,949		923,949		934,971
Ending Balance: individually evaluated for impairment	9,625		9,625		7,308
Ending Balance: collectively evaluated for impairment	913,803		913,803		927,149
Reserve for unfunded loan commitments included in other liabilities			398	386	398
Loans Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Ending balance: Loans receivables	521		521		514
Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	133	207	161	221	221
Charge-offs	(125)		(125)	(137)	(151)
Recoveries		308	4	334
Provisions	115	(352)	83	(255)
Ending balance	123	163	123	163	161
Ending balance: individually evaluated for impairment					1
Ending balance: collectively evaluated for impairment	123		123		160
Ending balance: Loans receivables	93,586		93,586		99,932
Ending Balance: individually evaluated for impairment	2,781		2,781		1,535
Ending Balance: collectively evaluated for impairment	90,805		90,805		98,397
Commercial Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	3,579	3,076	3,647	2,856	2,856
Charge-offs			(105)	(184)
Recoveries	1		8
Provisions	95	213	125	617
Ending balance	3,675	3,289	3,675	3,289	3,647
Ending balance: individually evaluated for impairment					78
Ending balance: collectively evaluated for impairment	3,675		3,675		3,569
Ending balance: Loans receivables	527,680		527,680		535,735
Ending Balance: individually evaluated for impairment	1,643		1,643		2,269
Ending Balance: collectively evaluated for impairment	525,516		525,516		532,952
Reserve for unfunded loan commitments included in other liabilities			4	3	4
Commercial Mortgage [Member] \| Loans Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Ending balance: Loans receivables	521		521		514
Commercial Term [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	1,144	889	1,062	845	845
Charge-offs	(24)	(15)	(115)	(79)
Recoveries	7		34	2
Provisions	119	113	265	219
Ending balance	1,246	987	1,246	987	1,062
Ending balance: individually evaluated for impairment	302		302		203
Ending balance: collectively evaluated for impairment	944		944		859
Ending balance: Loans receivables	174,445		174,445		166,335
Ending Balance: individually evaluated for impairment	3,203		3,203		2,300
Ending Balance: collectively evaluated for impairment	171,242		171,242		164,035
Reserve for unfunded loan commitments included in other liabilities			178	176	167
Commercial Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	1,032	1,355	1,032	1,128	1,128
Charge-offs
Provisions	(38)	(287)	(38)	(60)
Ending balance	994	1,068	994	1,068	1,032
Ending balance: collectively evaluated for impairment	994		994		1,032
Ending balance: Loans receivables	75,573		75,573		76,302
Ending Balance: individually evaluated for impairment	1,558		1,558		476
Ending Balance: collectively evaluated for impairment	74,015		74,015		75,826
Reserve for unfunded loan commitments included in other liabilities			197	186	206
Consumer: Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	209	196	190	183	183
Charge-offs			(128)
Provisions	(3)		144	13
Ending balance	206	196	206	196	190
Ending balance: collectively evaluated for impairment	206		206		190
Ending balance: Loans receivables	48,094		48,094		51,536
Ending Balance: individually evaluated for impairment	277		277		531
Ending Balance: collectively evaluated for impairment	47,817		47,817		51,005
Reserve for unfunded loan commitments included in other liabilities			19	21	21
Consumer: Other [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	39	49	46	63	63
Charge-offs	(3)	(23)	(20)	(72)
Recoveries		1		2
Provisions	10	21	20	55
Ending balance	46	48	46	48	46
Ending balance: individually evaluated for impairment	5		5		3
Ending balance: collectively evaluated for impairment	41		41		43
Ending balance: Loans receivables	4,571		4,571		5,131
Ending Balance: individually evaluated for impairment	163		163		197
Ending Balance: collectively evaluated for impairment	4,408		4,408		4,934
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	536	416	537	547	547
Charge-offs
Provisions	27	392	26	261
Ending balance	563	$ 808	563	$ 808	537
Ending balance: collectively evaluated for impairment	$ 563		$ 563		$ 537

FinancingReceivableReserveForUnfundedLoanCommitments

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- Definition

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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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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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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- Definition

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 loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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