Discontinued operations Discontinued financials (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016	Jan. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Revenue	$ 0	$ 0	$ 0	$ 10,467
(Loss) gain on disposal of discontinued operations	0	(2,204)	0	268
Income from discontinued operations	0	1,876	0	1,216
(Loss) income from discontinued operations before income tax	0	(328)	0	1,484
Discontinued operation, income tax (benefit) expense	0	(125)	0	578
(Loss) income from discontinued operations, net of tax	0	$ (203)	0	906
Disposal Group, Including Discontinued Operation, accounts receivable	0		0		$ 25
Disposal Group, Including Discontinued Operation, Assets	0		0		25
Disposal Group, Including Discontinued Operation, Accounts Payable and Accrued Liabilities	138		138		199
Disposal Group, Including Discontinued Operation, Liabilities	$ 138		138		$ 199
Net cash used in discontinued operating activities			(36)	(673)
Net cash provided by discontinued investing activities			0	9,606
Net cash used in discontinued financing activities			$ 0	$ (8,933)