Fair Value of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Financial assets
Securities	$ 386,440	$ 352,185
Accrued interest receivable	5,091	5,964
Financial liabilities
Accrued interest payable	166	232
Level 1
Financial assets
Cash and short-term investments	67,703	54,920
Accrued interest receivable	5,091	5,964
Financial liabilities
Accrued interest payable	166	232
Level 2
Financial assets
Mortgage loans held for sale	14,431	4,594
Federal Home Loan Bank stock and other securities	6,180	5,949
Financial liabilities
Deposits	1,786,046	1,626,170
Short-term borrowings	75,597	103,299
Long-term borrowings	62,826	100,491
Level 3
Financial assets
Loans, net	1,583,018	1,549,473
Level 3 \| Standby letters of credit
Off balance sheet financial instruments
Fair Value	(221)	(199)
Carrying Amount
Financial assets
Cash and short-term investments	67,703	54,920
Mortgage loans held for sale	14,047	4,381
Federal Home Loan Bank stock and other securities	6,180	5,949
Loans, net	1,552,713	1,515,100
Accrued interest receivable	5,091	5,964
Financial liabilities
Deposits	1,781,693	1,617,739
Short-term borrowings	75,597	103,299
Long-term borrowings	62,782	101,331
Accrued interest payable	166	232
Carrying Amount \| Commitments to extend credit
Off balance sheet financial instruments
Fair Value	386,372	318,907
Carrying Amount \| Standby letters of credit
Off balance sheet financial instruments
Fair Value	14,757	13,289
Fair value
Financial assets
Cash and short-term investments	67,703	54,920
Mortgage loans held for sale	14,431	4,594
Federal Home Loan Bank stock and other securities	6,180	5,949
Loans, net	1,583,018	1,549,473
Accrued interest receivable	5,091	5,964
Financial liabilities
Deposits	1,786,046	1,626,170
Short-term borrowings	75,597	103,299
Long-term borrowings	62,826	100,491
Accrued interest payable	166	232
Fair value \| Standby letters of credit
Off balance sheet financial instruments
Fair Value	$ (221)	$ (199)

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Represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount shown on the entity's books for investments made in Federal Home Loan Bank stock and other securities.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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The sum of cash and cash equivalents plus Federal Funds Sold. Cash and cash equivalents consist of short term, highly liquid investments that are readily convertible to known amounts of cash and are so near their maturity that they present negligible risk of changes in value due to changes in interest rates -- usually with an original maturity less than 90 days.

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The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid.

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