Discontinued operations Discontinued financials (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2015	Jan. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, Plant and Equipment, Disposals			$ 7,100
Proceeds from Sale of Buildings			1,900
Disposal Group, Including Discontinued Operation, Revenue	$ 0	$ 19,366	10,467	$ 51,677
(Loss) gain on disposal of discontinued operations	(2,204)	0	268	0
Income (loss) from discontinued operations	1,876	(245)	1,216	(1,583)
(Loss) income from discontinued operations before income tax	(328)	(245)	1,484	(1,583)
Discontinued operation, income tax (benefit) expense	(125)	99	578	187
(Loss) income from discontinued operations, net of tax	(203)	$ (344)	906	(1,770)
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	0		0		$ 5
Disposal Group, Including Discontinued Operation, accounts receivable, net	42		42		5,720
Disposal Group, Including Discontinued Operation, Inventory	0		0		2,000
Disposal Group, Including Discontinued Operation, Other Assets	4		4		60
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment	0		0		6,456
Disposal Group, Including Discontinued Operation, Assets	46		46		14,241
Disposal Group, Including Discontinued Operation, Accounts Payable and Accrued Liabilities	644		644		7,514
Disposal Group, current maturities	0		0		5,322
Disposal Group, Including Discontinued Operation, Liabilities	$ 644		644		$ 12,836
Net cash used in discontinued operating activities			(673)	(689)
Net cash provided by (used in) discontinued investing activities			9,606	(1,373)
Net cash (used in) provided by discontinued financing activities			$ (8,933)	$ 1,553