Interim Condensed Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (USD $) In Thousands	Total	Common Stock	Shares to be Issued for Deferred Compensation Obligations	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning Balance at Dec. 31, 2009	$ 140,803	$ 133,443	$ 4,507	$ 4,972	$ (2,119)
Beginning balance, shares at Dec. 31, 2009		7,535,193
Comprehensive income	7,918			4,174	3,744
Issuance of common stock, shares		59,197
Issuance of common stock	1,529	1,529
Common stock issued for deferred compensation obligations, shares		26,898
Common stock issued for deferred compensation obligations	89	537	(448)
Share based payment awards under equity compensation plan	332		332
Common stock purchased for deferred compensation obligations	(254)	(254)
Common stock repurchased pursuant to publicly announced repurchase plan, shares		(76,097)
Common stock repurchased pursuant to publicly announced repurchase plan	(1,426)	(1,426)
Cash dividends ($0.36 per share, 2010 and $0.38 per share, 2011)	(2,712)			(2,712)
Ending Balance at Jun. 30, 2010	146,279	133,829	4,391	6,434	1,625
Ending balance, shares at Jun. 30, 2010		7,545,191
Beginning Balance at Dec. 31, 2010	145,161	133,592	4,682	8,596	(1,709)
Beginning balance, shares at Dec. 31, 2010		7,550,074
Comprehensive income	8,710			4,988	3,722
Issuance of common stock, shares		61,218
Issuance of common stock	1,346	1,346
Common stock issued for deferred compensation obligations, shares		14,842
Common stock issued for deferred compensation obligations	12	266	(254)
Share based payment awards under equity compensation plan	307		307
Common stock purchased for deferred compensation obligations	(227)	(227)
Common stock repurchased pursuant to publicly announced repurchase plan, shares		(50,458)
Common stock repurchased pursuant to publicly announced repurchase plan	(914)	(914)
Cash dividends ($0.36 per share, 2010 and $0.38 per share, 2011)	(2,881)			(2,881)
Ending Balance at Jun. 30, 2011	$ 151,514	$ 134,063	$ 4,735	$ 10,703	$ 2,013
Ending balance, shares at Jun. 30, 2011		7,575,676

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Common stock issued for deferred compensation obligations, shares

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Share based payment awards under equity compensation plan

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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Equity impact of common stock cash dividends declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

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Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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