Loans and Allowance for Loan Losses (Allowance for Loan Losses by Commercial and Consumer Portfolio Segments) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	$ 16,051	$ 15,852	$ 15,762	$ 15,523
Provision for loan losses	300	400	600	900
Loan charge-offs	(237)	(311)	(277)	(604)
Loan recoveries	30	159	59	281
Net loan charge-offs	(207)	(152)	(218)	(323)
Balance, end of period	$ 16,144	$ 16,100	$ 16,144	$ 16,100
Net charge-offs to average loans (annualized)	0.05%	0.04%	0.03%	0.04%
Allowance for loan losses to gross loans	0.89%	1.05%
Allowance for loan losses to nonperforming loans	277.92%	208.52%
Commercial Loan [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period			$ 9,240
Balance, end of period	$ 11,016		11,016
Commercial Loan [Member] \| Owner Occupied Re [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	2,783	$ 2,680	2,726	$ 2,534
Provision for loan losses	135	19	192	165
Loan charge-offs	(110)		(110)
Loan recoveries
Net loan charge-offs	(110)		(110)
Balance, end of period	2,808	2,699	2,808	2,699
Commercial Loan [Member] \| Non Owner Occupied Re [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,886	3,366	3,811	3,230
Provision for loan losses	143	342	217	478
Loan charge-offs	(13)	(234)	(14)	(234)
Loan recoveries		107	2	107
Net loan charge-offs	(13)	(127)	(12)	(127)
Balance, end of period	4,016	3,581	4,016	3,581
Commercial Loan [Member] \| Business Loan [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,796	3,553	3,616	3,848
Provision for loan losses	(181)	280	(10)	(14)
Loan charge-offs				(119)
Loan recoveries	8	16	17	134
Net loan charge-offs	8	16	17	15
Balance, end of period	3,623	3,849	3,623	3,849
Commercial Loan [Member] \| Construction Loans [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	572	415	615	325
Provision for loan losses	(3)	129	(46)	219
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	569	544	569	544
Consumer Loan [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period			4,508
Balance, end of period	5,128		5,128
Consumer Loan [Member] \| Other Consumer [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	281	280	290	281
Provision for loan losses	23	(12)	50	19
Loan charge-offs	(14)		(53)	(34)
Loan recoveries	7		10	2
Net loan charge-offs	(7)		(43)	(32)
Balance, end of period	297	268	297	268
Consumer Loan [Member] \| Construction Loans [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	282	256	275	210
Provision for loan losses	36	26	43	72
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	318	282	318	282
Consumer Loan [Member] \| Real Estate Loan [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,041	3,391	3,081	3,495
Provision for loan losses	49	54	(6)	25
Loan charge-offs				(77)
Loan recoveries	14	1	29	3
Net loan charge-offs	14	1	29	(74)
Balance, end of period	3,104	3,446	3,104	3,446
Consumer Loan [Member] \| Home Equity Loan [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	1,410	1,911	1,348	1,600
Provision for loan losses	98	(438)	160	(64)
Loan charge-offs	(100)	(77)	(100)	(140)
Loan recoveries	1	35	1	35
Net loan charge-offs	(99)	(42)	(99)	(105)
Balance, end of period	$ 1,409	$ 1,431	$ 1,409	$ 1,431

Allowance for loan and lease losses write offs net of recoveries.

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- Definition

Allowance for loan losses as a percentage of gross loans.

+ References

No definition available.

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- Definition

Allowance for credit losses as a percentage of nonperforming loans.

+ References

No definition available.

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- Definition

Net loan charge offs annualized as a percentage of average total loans.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 326
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- Definition

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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- Definition

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.

+ References

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from recovery of amount previously written off or reestablishment of reserve previously utilized.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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