Condensed Consolidated Statement Of Shareholders' Equity (USD $) In Thousands	Common Stock [Member]	Restricted Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Total
Balance, value at Dec. 31, 2011	$ 1	$ 13,692	$ 67,422	$ 484,508	$ (72,434)	$ 493,189
Balance, shares at Dec. 31, 2011	41,571	243
Net income				40,745		40,745
Other comprehensive income, net of tax					16,081	16,081
Restricted stock activity, shares		10
Restricted stock activity, value		854				854
Dividends				(2,499)		(2,499)
Balance, value at Mar. 31, 2012	$ 1	$ 14,546	$ 67,422	$ 522,754	$ (56,353)	$ 548,370
Balance, shares at Mar. 31, 2012	41,571	253