Loans And The Allowance For Credit Losses (Loan Loss Experience And Activity In The Allowance For Credit Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	$ 12,815	$ 12,828
Charge-offs	(158)	(22)
Recoveries	82	23
Provision (credit)	0	100
Ending balance	12,739	12,929
Commercial, Financial And Agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	3,331	3,354
Charge-offs	(29)
Recoveries	25	2
Provision (credit)	41	22
Ending balance	3,368	3,378
Municipal Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	636	768
Provision (credit)	(93)	(75)
Ending balance	543	693
Real Estate Loans – Residential [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	3,127	3,081
Charge-offs	(55)	(2)
Recoveries	3	18
Provision (credit)	35	255
Ending balance	3,110	3,352
Real Estate Loans – Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	5,251	5,085
Recoveries	1
Provision (credit)	(35)	34
Ending balance	5,217	5,119
Real Estate Loans – Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	415	512
Provision (credit)	23	(152)
Ending balance	438	360
Installment Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	13		18
Charge-offs	(74)
Recoveries	53
Provision (credit)	71
Ending balance	63	18	18
All Other Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	42	10
Charge-offs		(20)
Recoveries		3
Provision (credit)	(42)	16
Ending balance		$ 9

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

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)(1)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

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

+ 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)(4)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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- Definition

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

+ 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)(3)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

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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

Reference 1: 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=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

Reference 3: 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=28368275&loc=SL6953423-111524

Reference 4: 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)

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