Consolidated Statements of Changes in Shareholders' Equity (USD $) In Thousands	Total	Common Stock	Additional Paid-In Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Income
Beginning balance at Jan. 31, 2010	$ 84,955	$ 107	$ 75,746	$ (4,843)	$ 10,247	$ 3,698
Beginning balance, shares at Jan. 31, 2010		10,737
Net income	4,729				4,729
Foreign currency translation	3,356					3,356
Issuance of common stock upon exercise of options	396	1	395
Issuance of common stock upon exercise of options, shares		77
Restricted stock issued	185	1	184
Restricted stock issued, shares		58
Tax expense from exercise of stock options and vesting of restricted stock	(5)		(5)
Stock-based compensation	1,099		1,099
Ending balance at Jan. 31, 2011	94,715	109	77,419	(4,843)	14,976	7,054
Ending balance, shares at Jan. 31, 2011		10,872
Net income	24,321				24,321
Foreign currency translation	150					150
Issuance of common stock upon exercise of options	2,822	3	2,819
Issuance of common stock upon exercise of options, shares		344
Stock offering	31,028	23	31,005
Stock offering, shares		2,300
Restricted stock issued	303	1	302
Restricted stock issued, shares		40
Restricted stock forfeited for taxes	(14)			(14)
Tax expense from exercise of stock options and vesting of restricted stock	778		778
Stock-based compensation	1,331		1,331
Ending balance at Jan. 31, 2012	155,434	136	113,654	(4,857)	39,297	7,204
Ending balance, shares at Jan. 31, 2012		13,556
Net income	17,051				17,051
Foreign currency translation	977					977
Issuance of common stock upon exercise of options	332	2	330
Issuance of common stock upon exercise of options, shares	158	158
Restricted stock issued	516		516
Restricted stock issued, shares		49
Restricted stock forfeited for taxes	(3)			(3)
Tax expense from exercise of stock options and vesting of restricted stock	420		420
Stock-based compensation	1,586		1,586
Ending balance at Jan. 31, 2013	$ 176,313	$ 138	$ 116,506	$ (4,860)	$ 56,348	$ 8,181
Ending balance, shares at Jan. 31, 2013		13,763