Discontinued operations Discontinued financials (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2016	Apr. 30, 2015	Jan. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	$ 7,191	$ 17,397
Gain on disposal of discontinued operations	867	0
Loss from discontinued operations	(1,083)	(1,303)
Loss from discontinued operations before income tax	(216)	(1,303)
Discontinued operation, income tax benefit	(16)	0
Loss from discontinued operations, net of tax	(200)	(1,303)
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	0		$ 5
Disposal Group, Including Discontinued Operation, accounts receivable, net	4,998		5,720
Disposal Group, Including Discontinued Operation, Inventory	1,939		2,000
Disposal Group, Including Discontinued Operation, Other Assets	1,565		1,552
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment	6,369		6,456
Disposal Group, Including Discontinued Operation, Assets	14,871		15,733
Disposal Group, Including Discontinued Operation, Accounts Payable and Accrued Liabilities	5,356		7,514
Disposal Group, current maturities	4,447		5,322
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent	2,629		2,629
Disposal Group, Including Discontinued Operation, Liabilities	12,432		$ 15,465
Cash Provided by (Used in) Operating Activities, Discontinued Operations	(1,408)	(1,568)
Cash Provided by (Used in) Investing Activities, Discontinued Operations	(1)	(383)
Cash Provided by (Used in) Financing Activities, Discontinued Operations	$ 858	$ 1,666