Discontinued operations Discontinued financials (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 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	$ 3,276	$ 14,914	10,467	$ 32,311
Gain on disposal of discontinued operations	1,605	0	2,472	0
Income (loss) from discontinued operations	423	(35)	(660)	(1,338)
Income (loss) from discontinued operations before income tax	2,028	(35)	1,812	(1,338)
Discontinued operation, income tax expense	719	88	703	88
Income (loss) from discontinued operations, net of tax	1,309	$ (123)	1,109	(1,426)
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	0		0		$ 5
Disposal Group, Including Discontinued Operation, accounts receivable, net	597		597		5,720
Disposal Group, Including Discontinued Operation, Inventory	0		0		2,000
Disposal Group, Including Discontinued Operation, Other Assets	212		212		1,552
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment	1,739		1,739		6,456
Disposal Group, Including Discontinued Operation, Assets	2,548		2,548		15,733
Disposal Group, Including Discontinued Operation, Accounts Payable and Accrued Liabilities	1,320		1,320		7,514
Disposal Group, current maturities	0		0		5,322
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent	0		0		2,629
Disposal Group, Including Discontinued Operation, Liabilities	$ 1,320		1,320		$ 15,465
Cash (used in) provided by operating activities, discontinued operations			(208)	224
Cash Provided by (Used in) Investing Activities, Discontinued Operations			7,574	(1,295)
Cash (used in) provided by financing activities, discontinued operations			$ (7,365)	$ 754