Condensed Consolidated Statement of Shareholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Preferred Shares [Member]	Common Shares [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Shares [Member]
Stockholders' Equity, Beginning Balance at Dec. 31, 2013	$ 492,803	$ 48,163	$ 271	$ 236,060	$ 262,625	$ (54,316)
Shares Outstanding, Beginning Balance at Dec. 31, 2013		2,000	24,357,943
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	12,632				12,632
Dividends, Preferred Stock	(1,219)				(1,219)
Stock options exercised, shares			101,630
Stock options exercised	1,366			(653)		2,019
Stock-based compensation expense	710			710
Deferral of executive and director compensation	299			299
Executive and director deferred compensation distributions shares			7,348
Executive and director deferred compensation distributions	0			(146)		146
Stockholders' Equity, Ending Balance at Mar. 31, 2014	$ 506,591	$ 48,163	$ 271	$ 236,270	$ 274,038	$ (52,151)
Shares Outstanding, Ending Balance at Mar. 31, 2014		2,000	24,466,921