Discontinued Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015
Discontinued operations [Line Items]
Assets of discontinued operations	$ 15,733	$ 41,476
Liabilities of discontinued operations	15,465	21,379
Long-term liabilities	$ 2,629	10,557
Disposal date	Jan. 29, 2016
Gross sales price	$ 22,000
Net proceeds from sale of discontinued operations	18,400
Funds held in escrow related to the sale of Filtration assets	1,905	0
Discontinued operation, net sales	64,975	68,110
Gain on disposal of discontinued operations	8,099	188
Impairment expense on discontinued operations	(6,480)	0
Loss from discontinued operation	(7,569)	(4,282)
Loss from discontinued operation, before income tax	(5,950)	(4,094)
Discontinued operation, income tax expense	94	324
Loss from discontinued operations, net of tax	$ (6,044)	$ (4,418)