Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Dec. 31, 2014	14,745
Balance at Dec. 31, 2014	$ 10,035	$ 38,191	$ 209,584	$ 2,085	$ 259,895
Net income			18,257		18,257
Other comprehensive loss, net of tax				(772)	(772)
Stock compensation expense		995			995
Stock issued for share-based awards, net of withholdings to satisfy employee tax obligations upon award (in shares)	127
Stock issued for share-based awards, net of withholdings to satisfy employee tax obligations upon award	$ 422	2,608	(1,507)		1,523
Cash dividends, $0.31 per share			(6,952)		(6,952)
Shares repurchased or cancelled (in shares)	(20)
Shares repurchased or cancelled	$ (67)	(581)	84		(564)
Balance (in shares) at Jun. 30, 2015	14,852
Balance at Jun. 30, 2015	$ 10,390	41,213	219,466	1,313	272,382
Balance (in shares) at Dec. 31, 2015	14,919
Balance at Dec. 31, 2015	$ 10,616	44,180	231,091	632	286,519
Net income			19,944		19,944
Other comprehensive loss, net of tax				4,818	4,818
Stock compensation expense		1,073			1,073
Stock issued for share-based awards, net of withholdings to satisfy employee tax obligations upon award (in shares)	103
Stock issued for share-based awards, net of withholdings to satisfy employee tax obligations upon award	$ 342	1,829	(1,689)		482
Cash dividends, $0.31 per share			(7,785)		(7,785)
Shares repurchased or cancelled (in shares)	(6)
Shares repurchased or cancelled	$ (20)	(164)	184
Balance (in shares) at Jun. 30, 2016	22,510
Balance at Jun. 30, 2016	$ 35,894	21,962	241,745	5,450	305,051
3 for 2 stock split (in shares)	7,494
3 for 2 stock split	$ 24,956	$ (24,956)