Discontinued operations (Details) (USD $)	3 Months Ended		9 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013	Oct. 31, 2012
Discontinued operations
Net proceeds from sale of discontinued operations			$ 15,253,000	$ 0
Proceeds held in escrow			1,100,000
escrow released date			May 01, 2014
Disposal date HVAC subsidiary			Jun. 26, 2013
Net sales	874,000	11,089,000	13,049,000	31,177,000
Gain on disposal of discontinued operations	0	0	11,665,000	0
(Loss) income from discontinued operations	(211,000)	415,000	(288,000)	891,000
(Loss) income from discontinued operations before income taxes	(211,000)	415,000	11,377,000	891,000
Income tax (benefit) expense	(789,000)	89,000	1,867,000	59,000
Income from discontinued operations, net of tax	$ 578,000	$ 326,000	$ 9,510,000	$ 832,000