Condensed Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss), net [Member]	Treasury Stock [Member]
Beginning balance at Dec. 31, 2014	$ 716,145	$ 105,563	$ 365,615	$ 353,027	$ (4,499)	$ (103,561)
Beginning balance, shares at Dec. 31, 2014		91,723,028
Net Income	14,221			14,221
Other comprehensive income (loss)	7,201				7,201
Dividends, declared (USD per share)	(6,407)			(6,407)
Treasury stock acquired	(18,874)					(18,874)
Treasury stock acquired, shares		(2,201,391)
Restricted stock	574	$ 0	259	0		315
Restricted stock, shares		134,370
Ending balance at Mar. 31, 2015	712,860	$ 105,563	365,874	360,841	2,702	(122,120)
Ending balance, shares at Mar. 31, 2015		89,656,007
Beginning balance at Dec. 31, 2015	$ 719,546	$ 105,563	365,981	378,081	(2,386)	(127,693)
Beginning balance, shares at Dec. 31, 2015	88,961,268	88,961,268
Net Income	$ 12,473			12,473
Other comprehensive income (loss)	7,664				7,664
Dividends, declared (USD per share)	(6,224)			(6,224)
Treasury stock acquired	(488)					(488)
Treasury stock acquired, shares		(55,301)
Restricted stock	343	$ 0	109	0		234
Restricted stock, shares		53,348
Ending balance at Mar. 31, 2016	$ 733,314	$ 105,563	$ 366,090	$ 384,330	$ 5,278	$ (127,947)
Ending balance, shares at Mar. 31, 2016	88,959,315	88,959,315