Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (USD $) In Thousands, except Share data	Preferred Stock [Member]	Common Stock [Member]	Warrant [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balances at Dec. 31, 2011	$ 56,600	$ 197	$ 946	$ 132,670	$ 71,423	$ 4,875	$ 266,711
Net Income					25,091		25,091
Net change in other comprehensive income						1,151	1,151
Stock-based compensation				2,060	(1)		2,059
Common stock issued under equity compensation plans		2		776			778
Common stock issued 1,770,585 shares (in Shares)		18		28,482			28,500
Tax benefits related to non-qualified stock compensation				87			87
Employee stock purchase plan				447			447
Preferred stock dividends					(425)		(425)
Balances at Sep. 30, 2012	56,600	217	946	164,522	96,088	6,026	324,399
Balances at Dec. 31, 2012	56,600	226	946	180,593	106,146	5,465	349,976
Net Income					35,004		35,004
Net change in other comprehensive income						(6,828)	(6,828)
10% common stock dividend 2,340,518 shares		23		56,158	(56,181)
Cash paid in lieu of fractional shares					(10)		(10)
Stock-based compensation				2,429			2,429
Common stock issued under equity compensation plans		3		1,244			1,247
Tax benefits related to non-qualified stock compensation				322			322
Employee stock purchase plan				385			385
Preferred stock dividends					(425)		(425)
Balances at Sep. 30, 2013	$ 56,600	$ 252	$ 946	$ 241,131	$ 84,534	$ (1,363)	$ 382,100