Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2012	Dec. 31, 2011
Condensed Consolidated Balance Sheets [Abstract]
Common stock, no par value
Common stock, shares authorized	6,500,000	6,500,000
Common stock, shares issued	5,200,000	5,200,000
Common stock, shares outstanding	5,200,000	5,200,000
Treasury stock, shares	495,077	483,663
Unearned stock awards, shares	29,570	29,715

Unearned stock awards, shares

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Issuance value per share of no-par value common stock; generally not indicative of the fair market value per share.

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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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Total number of shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Shares outstanding equals shares issued minus shares held in treasury and other adjustments, if any.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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