Acquisition (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015	Jan. 31, 2016
Business Acquisition [Line Items]
Business Acquisition, Name of Acquired Entity			Bayou Perma-Pipe Canada, Ltd
Business Acquisition, Description of Acquired Entity			a coating and insulation company in Camrose, Alberta
Business Acquisition, Date of Acquisition Agreement			Feb. 04, 2016
Equity Method Investment, Ownership Percentage					49.00%
Cash			$ 7,587
Loan payable			2,000
Purchase consideration to third party			9,587
Fair Value of 49% Previously Held Equity Interest			7,492
Total purchase consideration			17,079
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	$ 2,915		2,915
Property and equipment	12,670		12,670
Goodwill	2,657		2,657		$ 0
Business combination, net working capital	406		406
Business Combination, other assets (liabilities) net Acquired and Liabilities Assumed, Noncurrent Liabilities	(1,569)		(1,569)
Net assets acquired	17,079		17,079
Business Acquisition, Transaction Costs	200		200
Loss on consolidation of joint venture	0	$ 0	1,620	$ 0
Net sales	22,859	25,147	45,928	45,424
Business acquisition, pro forma net sales		26,935		56,271
Net income (loss)	$ 449	(2,391)	$ (5,845)	(7,046)
Business acquisition, pro forma net loss		$ (2,448)		$ (6,916)
Business acquisition, pro forma loss per share, basic and diluted		$ (0.34)		$ (0.95)
Earnings (loss) per share, basic and diluted	$ 0.06	$ (0.33)	$ (0.79)	$ (0.97)