Income taxes UTP (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Income Tax Contingency [Line Items]
Balance at beginning of the year		$ 1,331	$ 1,313
Increases in positions taken in a prior period	$ 6	3
Increases in positions taken in a current period	5	19
Decreases due to lapse of statute of limitations	(34)	(4)
Decreases due to settlements	(7)	$ 0
Balance at the end of the year	$ 1,301