Share Based Compensation - Outstanding stock options (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Jan. 31, 2017 USD ($) $ / shares shares
Number of options
Outstanding, beginning of period (in shares) | shares	925,950
Granted (in shares) | shares	274,200
Exercised (in shares) | shares	0
Forfeited (in shares) | shares	(4,125)
Expired (in shares) | shares	(205,125)
Outstanding, end of period (in shares) | shares	990,900
Weighted average exercise price
Outstanding, beginning of period (in usd per share) | $ / shares	$ 28.44
Granted (in usd per share) | $ / shares	15.61
Exercised (in usd per share) | $ / shares	0.00
Forfeited (in usd per share) | $ / shares	25.41
Expired (in usd per share) | $ / shares	30.03
Outstanding, end of period (in usd per share) | $ / shares	$ 24.58
Aggregate intrinsic value, Outstanding, end of period | $	$ 3,867
Weighted average remaining contractual term (years), Outstanding, end of period	2 years 6 months 20 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number | shares	990,900
Number of options, Outstanding exercisable, end of period | shares	422,158
Weighted average exercise price, Outstanding exercisable, end of period | $ / shares	$ 30.24
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price | $ / shares	$ 24.58
Aggregate intrinsic value, Outstanding exercisable, end of period | $	$ 361
Weighted average remaining contractual term (years), Outstanding exercisable, end of period	1 year 4 months 29 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term	2 years 6 months 20 days