Condensed Consolidated Statement of Changes in Shareholders' Equity (Unaudited) - 6 months ended Jun. 30, 2015 - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2014	$ 446,968	$ 201	$ (22,370)	$ 199,138	$ 267,189	$ 2,810
Beginning Balance, Shares at Dec. 31, 2014	18,897,686	20,155,936
Treasury Stock Beginning Balance, Shares at Dec. 31, 2014	(1,258,250)		(1,258,250)
Comprehensive income	$ 28,691				29,449	(758)
Options exercised	$ 834	$ 1		833
Options exercised, Shares	97,850	97,850
Tax benefit from share-based payments	$ 1,071			1,071
Restricted common stock issued	502			502
Restricted common stock issued, Shares		14,256
Share-based compensation	390			390
Dividends to stockholders	(5,658)				(5,658)
Ending Balance at Jun. 30, 2015	$ 472,798	$ 202	$ (22,370)	$ 201,934	$ 290,980	$ 2,052
Ending Balance, Shares at Jun. 30, 2015	19,009,792	20,268,042
Treasury Stock Ending Balance, Shares at Jun. 30, 2015	(1,258,250)		(1,258,250)