Consolidated Statements of Income (USD $) In Thousands, except Per Share data	3 Months Ended
	Apr. 30, 2011	Apr. 30, 2010
Net sales	$ 101,541	$ 85,030
Cost of goods sold	68,605	57,859
Gross profit	32,936	27,171
Research and development expenses	2,243	2,126
Selling, general and administrative expenses	7,160	5,540
Operating income	23,533	19,505
Other income (expense), net	(13)	52
Income before income taxes	23,520	19,557
Income taxes	7,804	6,612
Net income	$ 15,716	$ 12,945
Net income per common share:
Basic	$ 0.87	$ 0.72
Diluted	$ 0.86	$ 0.72
Cash dividends paid per common share	$ 0.18	$ 0.16