CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Total	Preferred Stock	Common Stock	Retained Earnings	Cost of Common Stock in Treasury	Accumulated Other Comprehensive Income (Loss), Net
Balance at Dec. 31, 2009	$ 570,320	$ 104,930	$ 350,269	$ 142,407	$ (32,380)	$ 5,094
Increase (Decrease) in Stockholders' Equity
Net income	41,244			41,244
Other comprehensive income	5,416					5,416
Issuance of 184,220, 154,921 and 187,554 common shares per stock based compensation awards, including related tax effects for the year ended 2012, 2011 and 2010, respectively	2,873			635	2,238
Cost of 154,637, 113,709 and 125,767 shares of common stock acquired for treasury for the year ended 2012, 2011 and 2010, respectively	(2,142)				(2,142)
Preferred stock discount accretion		6,070		(6,070)
Redemption of preferred stock	(111,000)	(111,000)
Preferred stock dividend (paid and/or accrued)	(5,519)			(5,519)
Stock based compensation	13		13
Common stock dividend ($.66, $.64 and $.61 per share for the year ended 2012, 2011 and 2010, respectively)	(14,822)			(14,822)
Balance at Dec. 31, 2010	486,383		350,282	157,875	(32,284)	10,510
Increase (Decrease) in Stockholders' Equity
Net income	48,195			48,195
Other comprehensive income	8,001					8,001
Issuance of 184,220, 154,921 and 187,554 common shares per stock based compensation awards, including related tax effects for the year ended 2012, 2011 and 2010, respectively	2,953			(183)	3,136
Cost of 154,637, 113,709 and 125,767 shares of common stock acquired for treasury for the year ended 2012, 2011 and 2010, respectively	(2,241)				(2,241)
Repurchase of common stock warrant	(3,750)		(3,750)
Stock based compensation	3		3
Common stock dividend ($.66, $.64 and $.61 per share for the year ended 2012, 2011 and 2010, respectively)	(15,626)			(15,626)
Balance at Dec. 31, 2011	523,918		346,535	190,261	(31,389)	18,511
Increase (Decrease) in Stockholders' Equity
Net income	49,633			49,633
Other comprehensive income	1,028					1,028
Issuance of 184,220, 154,921 and 187,554 common shares per stock based compensation awards, including related tax effects for the year ended 2012, 2011 and 2010, respectively	3,935			(21)	3,956
Cost of 154,637, 113,709 and 125,767 shares of common stock acquired for treasury for the year ended 2012, 2011 and 2010, respectively	(3,701)				(3,701)
Common stock dividend ($.66, $.64 and $.61 per share for the year ended 2012, 2011 and 2010, respectively)	(16,158)			(16,158)
Balance at Dec. 31, 2012	$ 558,655		$ 346,535	$ 223,715	$ (31,134)	$ 19,539