Loans (Details) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Composition of loans by primary loan classification
Loans	$ 1,721,350,000	$ 1,584,594,000	$ 1,544,845,000
Net deferred loan (costs) fees	(139,000)	47,000
Loans under participation agreements with other banks	9,449,000	7,658,000
Loans to directors and their associates, including loans to companies for which directors are principal owners, and executive officers
Balance at the beginning of the period	6,099,000	622,000
New loans and advances on lines of credit	10,006,000	6,691,000
Repayments on loans and lines of credit	7,438,000	1,214,000
Balance at the end of the period	8,667,000	6,099,000
Commercial and industrial
Composition of loans by primary loan classification
Loans	510,739,000	426,930,000	393,729,000
Construction and development excluding undeveloped land
Composition of loans by primary loan classification
Loans	91,719,000	85,456,000	147,637,000
Undeveloped land
Composition of loans by primary loan classification
Loans	37,871,000	45,797,000
Real estate mortgage
Composition of loans by primary loan classification
Loans	1,046,823,000	989,631,000	966,665,000
Consumer
Composition of loans by primary loan classification
Loans	$ 34,198,000	$ 36,780,000	$ 36,814,000

Represents the net amount of deferred loan costs or deferred interest and fee income for the period.

No definition available.

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- Definition

Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7523297&loc=SL6224234-111729

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. 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 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524

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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph e

-Article 9

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Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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- Definition

Reflects the amount of collections received from related parties to reduce the carrying amounts of loans and leases receivable due from them.

+ References

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