Stock options Options additional text (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015
increase number of shares that may be issued	2.00%
Initial number of options to grant under plan	350,000
vesting period for stock options	P4Y
unrecognized stock option expense	$ 0.5
cost is expected to be recognized over the weighted-average period	2 years 1 month 24 days
Maturity period for stock option from issuance date	10 years
Stock Option [Member]
Weighted average fair value of options granted	$ 2.54	$ 4.73