Consolidated Statements of Changes in Stockholders Equity (Unaudited) (USD $) In Thousands	Total	Preferred stock	Common stock	Retained earnings	Accumulated other comprehensive income
Beginning Balance at Dec. 31, 2009	$ 574,434	$ 50,000	$ 112,135	$ 397,224	$ 15,075
Comprehensive income:
Net income	26,518			26,518
Other comprehensive income, net of tax	7,873				7,873
Total comprehensive income	34,391
Common stock transactions:
Common shares purchased and retired 14,464 and 246,596 in 2011 and 2010 respectively	(3,699)		(3,699)
Common shares issued 15,440 and 11,506,503 in 2011 and 2010 respectively	153,120		153,120
Non-vested common shares issued 130,904 and 117,140 in 2011 and 2010 respectively	0		0
20,039 and 14,724 non-vested common shares forfeited in 2011 and 2010 respectively	(80)		(80)
Non-vested liability awards vesting during period	59		59
67,197 and 86,129 stock options exercised, net of 114,211 and 69,363 shares tendered in payment of option price and income tax withholding amounts in 2011 and 2010 respectively	650		650
Tax benefit of stock-based compensation	234		234
Stock-based compensation expense	1,300		1,300
Cash dividends declared:
Common ($0.3375 per share)	(13,147)			(13,147)
Preferred (6.75% per share)	(2,559)			(2,559)
Ending Balance at Sep. 30, 2010	744,703	50,000	263,719	408,036	22,948
Beginning Balance at Dec. 31, 2010	736,802	50,000	264,174	413,253	9,375
Comprehensive income:
Net income	31,281			31,281
Other comprehensive income, net of tax	14,707				14,707
Total comprehensive income	45,988
Common stock transactions:
Common shares purchased and retired 14,464 and 246,596 in 2011 and 2010 respectively	(197)		(197)
Common shares issued 15,440 and 11,506,503 in 2011 and 2010 respectively	205		205
Non-vested common shares issued 130,904 and 117,140 in 2011 and 2010 respectively	0		0
20,039 and 14,724 non-vested common shares forfeited in 2011 and 2010 respectively	(101)		(101)
Non-vested liability awards vesting during period	195		195
67,197 and 86,129 stock options exercised, net of 114,211 and 69,363 shares tendered in payment of option price and income tax withholding amounts in 2011 and 2010 respectively	272		272
Tax benefit of stock-based compensation	204		204
Stock-based compensation expense	1,565		1,565
Cash dividends declared:
Common ($0.3375 per share)	(14,419)			(14,419)
Preferred (6.75% per share)	(2,559)			(2,559)
Ending Balance at Sep. 30, 2011	$ 767,955	$ 50,000	$ 266,317	$ 427,556	$ 24,082