CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Dec. 31, 2012	$ 24,688	$ 184,023	$ (863)	$ 207,848
Balance (in shares) at Dec. 31, 2012	47,924
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	29,586	0	29,586
Other comprehensive income (loss), net of tax	0	0	3,457	3,457
Dividends declared	0	(8,647)	0	(8,647)
Dividends reinvested in common stock	$ 475	0	0	475
Dividends reinvested in common stock (in shares)	40
Stock based compensation	$ 1,938	0	0	1,938
Common stock issued through exercise of incentive stock options	$ 1,186	0	0	1,186
Common stock issued through exercise of incentive stock options (in shares)	132
Common stock issued for share awards	$ 0	0	0	0
Common stock issued for share awards (in shares)	136
Common stock issued	$ 10	0	0	10
Common stock issued (in shares)	2
Common stock repurchased	$ (1,600)	0	0	(1,600)
Common stock repurchased (in shares)	(154)
Net excess tax benefit from stock options exercised	$ 62	0	0	62
Balance at Dec. 31, 2013	$ 26,759	204,962	2,594	234,315
Balance (in shares) at Dec. 31, 2013	48,080
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	33,883	0	33,883
Other comprehensive income (loss), net of tax	0	0	(1,472)	(1,472)
Dividends declared	0	(11,333)	0	(11,333)
Dividends reinvested in common stock	$ 572	0	0	572
Dividends reinvested in common stock (in shares)	39
Stock based compensation	$ 2,624	0	0	2,624
Common stock issued through exercise of incentive stock options	$ 1,141	0	0	1,141
Common stock issued through exercise of incentive stock options (in shares)	102
Common stock issued for share awards	$ 0	0	0	0
Common stock issued for share awards (in shares)	162
Common stock issued	$ 6	0	0	6
Common stock issued (in shares)	2
Common stock repurchased	$ (1,785)	0	0	(1,785)
Common stock repurchased (in shares)	(120)
Net excess tax benefit from stock options exercised	$ 395	0	0	395
Balance at Dec. 31, 2014	$ 29,712	227,512	1,122	$ 258,346
Balance (in shares) at Dec. 31, 2014	48,265			48,265
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	40,864	0	$ 40,864
Other comprehensive income (loss), net of tax	0	0	(707)	(707)
Dividends declared	0	(11,629)	0	(11,629)
Dividends reinvested in common stock	$ 544	0	0	544
Dividends reinvested in common stock (in shares)	22
Stock based compensation	$ 2,719	0	0	2,719
Common stock issued through exercise of incentive stock options	$ 996	0	0	996
Common stock issued through exercise of incentive stock options (in shares)	87
Common stock issued for share awards	$ 0	0	0	0
Common stock issued for share awards (in shares)	212
Common stock issued	$ 11	0	0	11
Common stock issued (in shares)	1
Common stock repurchased	$ (1,885)	0	0	(1,885)
Common stock repurchased (in shares)	(111)
Net excess tax benefit from stock options exercised	$ 679	0	0	679
Balance at Dec. 31, 2015	$ 32,776	$ 256,747	$ 415	$ 289,938
Balance (in shares) at Dec. 31, 2015	48,475			48,475