Condensed Consolidated Statements of Income Unaudited - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Income Statement [Abstract]
Net sales	$ 74,802	$ 72,636	$ 97,371	$ 95,871
Costs of goods sold	47,670	45,953	62,554	60,761
Gross profit	27,132	26,683	34,817	35,110
Selling, general and administrative expenses	18,717	18,278	30,991	29,970
Gain on sale of property, plant & equipment	0	(1)	(1)	(1)
Operating income	8,415	8,406	3,827	5,141
Interest expense, net	822	529	1,268	824
Income (loss) before income taxes	7,593	7,877	2,559	4,317
Income tax (benefit) expense	2,118	2,849	656	1,500
Net income (loss)	$ 5,475	$ 5,028	$ 1,903	$ 2,817
Dividend declared per share: Cash (usd per share)	$ 0.015	$ 0	$ 0.03	$ 0
Net income (loss) per common share:
Basic (usd per share)	0.36	0.33	0.12	0.19
Diluted (usd per share)	$ 0.35	$ 0.33	$ 0.12	$ 0.18
Weighted average shares outstanding:
Basic (shares)	15,392	15,211	15,355	15,170
Diluted (shares)	15,435	15,285	15,395	15,233