Condensed Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010
Statement Of Financial Position [Abstract]
Amortized cost on available for sale securities (in dollars)	$ 302,883	$ 275,606	$ 257,773
Amortized cost on held to maturity securities (in dollars)	$ 11,700	$ 20,784	$ 35,450
Common stock, par value (in dollars per share)	$ 5	$ 5	$ 5
Common stock, authorized	3,000,000	3,000,000	3,000,000
Common stock, issued	1,661,913	1,664,622	1,666,449

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 7

-Footnote 2

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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This item represents the amortized cost, prior to other than temporary impairment (OTTI), of investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity. The temporary impairments arise from the unrealized losses that are recognized in AOCI.

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