Allowance for Credit Losses (Allowance For Credit Losses And Recorded Investments In Loans Receivables) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	$ 6,675	$ 5,843	$ 5,843
Charge-offs	(168)	(76)
Recoveries	12	3
Provisions	200	375
Ending balance	6,719	6,145	6,675
Ending balance: individually evaluated for impairment	201		285
Ending balance: collectively evaluated for impairment	6,518		6,390
Ending balance: Loans receivables	933,697		934,971
Ending Balance: individually evaluated for impairment	7,709		7,308
Ending Balance: collectively evaluated for impairment	925,467		927,149
Reserve for unfunded loan commitments included in other liabilities	424	309	398
Loans Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Ending balance: Loans receivables	521		514
Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	161	221	221
Charge-offs		(34)	(151)
Recoveries	4	1
Provisions	(9)	38
Ending balance	156	226	161
Ending balance: individually evaluated for impairment			1
Ending balance: collectively evaluated for impairment	156		160
Ending balance: Loans receivables	101,039		99,932
Ending Balance: individually evaluated for impairment	2,782		1,535
Ending Balance: collectively evaluated for impairment	98,257		98,397
Commercial Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	3,647	2,856	2,856
Charge-offs	(82)	(13)
Provisions	(72)	144
Ending balance	3,493	2,987	3,647
Ending balance: individually evaluated for impairment			78
Ending balance: collectively evaluated for impairment	3,493		3,569
Ending balance: Loans receivables	517,236		535,735
Ending Balance: individually evaluated for impairment	2,177		2,269
Ending Balance: collectively evaluated for impairment	514,538		532,952
Reserve for unfunded loan commitments included in other liabilities	1	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		514
Commercial Term [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	1,062	845	845
Charge-offs	(69)	(17)
Recoveries	8	2
Provisions	188	74
Ending balance	1,189	904	1,062
Ending balance: individually evaluated for impairment	201		203
Ending balance: collectively evaluated for impairment	988		859
Ending balance: Loans receivables	182,077		166,335
Ending Balance: individually evaluated for impairment	2,045		2,300
Ending Balance: collectively evaluated for impairment	180,032		164,035
Reserve for unfunded loan commitments included in other liabilities	184	150	167
Commercial Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	1,032	1,128	1,128
Charge-offs
Provisions	48	91
Ending balance	1,080	1,219	1,032
Ending balance: collectively evaluated for impairment	1,080		1,032
Ending balance: Loans receivables	78,967		76,302
Ending Balance: individually evaluated for impairment			476
Ending Balance: collectively evaluated for impairment	78,967		75,826
Reserve for unfunded loan commitments included in other liabilities	219	139	206
Consumer: Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	190	183	183
Charge-offs
Provisions	(7)	(7)
Ending balance	183	176	190
Ending balance: collectively evaluated for impairment	183		190
Ending balance: Loans receivables	49,412		51,536
Ending Balance: individually evaluated for impairment	530		531
Ending Balance: collectively evaluated for impairment	48,882		51,005
Reserve for unfunded loan commitments included in other liabilities	20	17	21
Consumer: Other [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	46	63	63
Charge-offs	(17)	(12)
Provisions	14	4
Ending balance	43	55	46
Ending balance: individually evaluated for impairment			3
Ending balance: collectively evaluated for impairment	43		43
Ending balance: Loans receivables	4,966		5,131
Ending Balance: individually evaluated for impairment	175		197
Ending Balance: collectively evaluated for impairment	4,791		4,934
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	537	547	547
Charge-offs
Provisions	38	31
Ending balance	575	$ 578	537
Ending balance: collectively evaluated for impairment	$ 575		$ 537

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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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