Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (USD $) In Thousands	Capital Stock [Member]	Surplus [Member]	Undivided Profits [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2012	$ 98,912	$ 174,899	$ 132,378	$ 1,558	$ (48,949)	$ 358,798
Net Income	0	0	29,183	0	0	29,183
Other comprehensive income (loss), net of tax	0	0	0	(17,481)	0	(17,481)
Cash dividend declared	0	0	(18,546)	0	0	(18,546)
Sale of treasury stock	0	(1,737)	0	0	3,925	2,188
Stock based compensation expense	0	246	0	0	0	246
Balance at Sep. 30, 2013	98,912	173,408	143,015	(15,923)	(45,024)	354,388
Balance at Dec. 31, 2013	98,927	173,144	147,432	(13,803)	(43,887)	361,813
Net Income	0	0	33,533	0	0	33,533
Other comprehensive income (loss), net of tax	0	0	0	10,295	0	10,295
Cash dividend declared	0	0	(18,639)	0	0	(18,639)
Stock options exerised and related tax benefits	15	63	0	0	0	78
Sale of treasury stock	0	(869)	0	0	3,016	2,147
Stock based compensation expense	0	260	0	0	0	260
Balance at Sep. 30, 2014	$ 98,942	$ 172,598	$ 162,326	$ (3,508)	$ (40,871)	$ 389,487