Statement of Stockholders' Equity (USD $) In Thousands	Total	Common Stock	Additional Paid in Capital	Retained Earnings	Unallocated ESOP Shares	Accumulated Other Comprensive Income (Loss)	Treasury Stock	Total Stockholders' Equity
Stockholders' Equity Beginning Balance at Dec. 31, 2009		$ 15,170	$ 178,192	$ 24,100	$ (2,204)	$ (6,640)	$ (67,800)	$ 140,818
Net Income	11,129			11,129				11,129
Net Unrealized Securities Holding Gains Arising During the Period, Net of Tax	5,237					5,237		5,237
Reclassification Adjustment for Net Securities Gains Included in Net Income, Net of Tax	(530)					(530)		(530)
Amortization of Net Retirement Plan Actuarial Loss	304					304		304
Accretion of Net Retirement Plan Prior Service Credit	(53)					(53)		(53)
Other Comprehensive Income								4,958
Comprehensive Income								16,087
Cash Dividends Paid	(5,472)			(5,472)				(5,472)
Stock Options Exercised	319		94				225	319
Shares Issued Under the Directors' Stock Plan	74		50				24	74
Shares Issued Under the Employee Stock Purchase Plan	235		154				81	235
Shares Issued for Dividend Reinvestment Plans	845		566				279	845
Stock-Based Compensation Expense	147		147					147
Tax Benefit for Disposition of Stock Options			63					63
Purchases of Treasury Stock	(1,548)						(1,548)	(1,548)
Shares Issued for Acquisition of Subsidiary	682		459				223	682
Allocation of ESOP Stock			125		328			453
Stockholders' Equity Ending Balance at Jun. 30, 2010	152,703	15,170	179,850	29,757	(1,876)	(1,682)	(68,516)	152,703
Stockholders' Equity Beginning Balance at Dec. 31, 2010	152,259	15,626	191,068	24,577	(2,876)	(6,423)	(69,713)	152,259
Net Income	11,130			11,130				11,130
Net Unrealized Securities Holding Gains Arising During the Period, Net of Tax	3,787					3,787		3,787
Reclassification Adjustment for Net Securities Gains Included in Net Income, Net of Tax	618					(618)		(618)
Amortization of Net Retirement Plan Actuarial Loss	309					309		309
Accretion of Net Retirement Plan Prior Service Credit	(38)					(38)		(38)
Other Comprehensive Income								3,440
Comprehensive Income								14,570
Cash Dividends Paid	(5,668)			(5,668)				(5,668)
Stock Options Exercised	313		183				130	313
Shares Issued Under the Directors' Stock Plan	88		55				33	88
Shares Issued Under the Employee Stock Purchase Plan	246		154				92	246
Shares Issued for Dividend Reinvestment Plans	889		541				348	889
Stock-Based Compensation Expense	174		174					174
Tax Benefit for Disposition of Stock Options			2					2
Purchases of Treasury Stock	(2,759)						(2,759)	(2,759)
Shares Issued for Acquisition of Subsidiary	3,134		2,034				1,100	3,134
Allocation of ESOP Stock			65		276			341
Stockholders' Equity Ending Balance at Jun. 30, 2011	$ 163,589	$ 15,626	$ 194,276	$ 30,039	$ (2,600)	$ (2,983)	$ (70,769)	$ 163,589