Consolidated Statements of Stockholders' Equity - 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	14,852
Balance at Dec. 31, 2014	$ 149	$ 77,540	$ 104,904	$ (4,495)	$ 178,098
Issuance of common stock for equity awards (in shares)	185
Issuance of common stock for equity awards	$ 1	1,073			1,074
Tax benefit related to equity awards		847			847
Stock-based compensation expense		2,225			2,225
Net income			30,758		30,758
Other comprehensive loss				(2,154)	(2,154)
Balance (in shares) at Dec. 31, 2015	15,037
Balance at Dec. 31, 2015	$ 150	81,685	135,662	(6,649)	210,848
Issuance of common stock for equity awards (in shares)	121
Issuance of common stock for equity awards	$ 1	1,006			1,007
Tax benefit related to equity awards		647			647
Stock-based compensation expense		3,392			3,392
Net income			32,547		32,547
Other comprehensive loss				(668)	(668)
Repurchase of common stock (in shares)	(531)
Repurchase of common stock	$ (5)	(24,995)			(25,000)
Balance (in shares) at Dec. 31, 2016	14,627
Balance at Dec. 31, 2016	$ 146	61,735	168,209	(7,317)	222,773
Issuance of common stock for equity awards (in shares)	61
Issuance of common stock for equity awards	$ 1	313			314
Stock-based compensation expense		5,807			5,807
Net income			31,816		31,816
Other comprehensive loss				2,533	2,533
Balance (in shares) at Dec. 31, 2017	14,688
Balance at Dec. 31, 2017	$ 147	68,617	199,511	(4,784)	263,491
Cumulative effect of change in accounting for stock-based compensation		$ 762	$ (514)		$ 248