Loans and Allowance for Loan Losses (Allowance For Loan Losses By Segment) (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 [Roll Forward]
Beginning Balance	$ 5,456	$ 4,411	$ 4,411
Charge-Offs	(10)	(138)	(236)
Recoveries	45	52	504
Provision for (recovery of) loan losses	194	205	777
Ending Balance	5,685	4,530	5,456
Ending balance: Individually evaluated for impairment	877		962
Ending balance: collectively evaluated for impairment	4,808		4,494
Loans Ending Balance	619,612		607,315
Ending balance individually evaluated for impairment	8,527		8,559
Ending balance collectively evaluated for impairment	611,085		598,756
Construction and Farmland
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	583	332	332
Charge-Offs	0		0
Recoveries	2		266
Provision for (recovery of) loan losses	58		(15)
Ending Balance	643		583
Ending balance: Individually evaluated for impairment	0		0
Ending balance: collectively evaluated for impairment	643		583
Loans Ending Balance	68,628		61,926
Ending balance individually evaluated for impairment	272		280
Ending balance collectively evaluated for impairment	68,356		61,646
Residential
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	1,788	1,754	1,754
Charge-Offs	0		(24)
Recoveries	13		28
Provision for (recovery of) loan losses	74		30
Ending Balance	1,875		1,788
Ending balance: Individually evaluated for impairment	95		119
Ending balance: collectively evaluated for impairment	1,780		1,669
Loans Ending Balance	236,157		229,784
Ending balance individually evaluated for impairment	4,213		4,044
Ending balance collectively evaluated for impairment	231,944		225,740
Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	1,988	1,627	1,627
Charge-Offs	0		0
Recoveries	6		78
Provision for (recovery of) loan losses	(35)		283
Ending Balance	1,959		1,988
Ending balance: Individually evaluated for impairment	182		193
Ending balance: collectively evaluated for impairment	1,777		1,795
Loans Ending Balance	263,857		265,595
Ending balance individually evaluated for impairment	2,806		2,919
Ending balance collectively evaluated for impairment	261,051		262,676
Commercial - Non Real Estate
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	919	570	570
Charge-Offs	0		(139)
Recoveries	13		100
Provision for (recovery of) loan losses	(49)		388
Ending Balance	883		919
Ending balance: Individually evaluated for impairment	600		650
Ending balance: collectively evaluated for impairment	283		269
Loans Ending Balance	34,798		33,086
Ending balance individually evaluated for impairment	1,236		1,316
Ending balance collectively evaluated for impairment	33,562		31,770
Consumer
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	53	69	69
Charge-Offs	(2)		(33)
Recoveries	10		19
Provision for (recovery of) loan losses	(13)		(2)
Ending Balance	48		53
Ending balance: Individually evaluated for impairment	0		0
Ending balance: collectively evaluated for impairment	48		53
Loans Ending Balance	8,056		8,470
Ending balance individually evaluated for impairment	0		0
Ending balance collectively evaluated for impairment	8,056		8,470
All Other Loans
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	97	29	29
Charge-Offs	(8)		(40)
Recoveries	1		13
Provision for (recovery of) loan losses	1		95
Ending Balance	91		97
Ending balance: Individually evaluated for impairment	0		0
Ending balance: collectively evaluated for impairment	91		97
Loans Ending Balance	8,116		8,454
Ending balance individually evaluated for impairment	0		0
Ending balance collectively evaluated for impairment	8,116		8,454
Unallocated
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	28	$ 30	30
Provision for (recovery of) loan losses	158		(2)
Ending Balance	186		28
Ending balance: collectively evaluated for impairment	$ 186		$ 28

A valuation allowance for financing receivables that are expected to be uncollectible.

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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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- Definition

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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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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No definition available.

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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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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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