Deferred and restricted stock (Details) - USD ($)	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Restricted stock [Line Items]
Deferred Compensation Arrangement with Individual, Common Stock Reserved for Future Issuance	9,991
Restricted stock grants	108,000	54,000
Restricted stock granted, weighted average fair value	$ 6.38	$ 12.41
Restricted stock issued	(26,000)	(15,000)
Restricted stock forfeited	(5,000)	(3,000)
Restricted stock, forfeitures, weighted average fair value	$ 6.38	$ 11.25
Deferred shares outstanding		85,554	50,000
share based compensation, other than options, weighted average, outstanding	$ 6.40	$ 14.52	$ 14.52
Restricted stock, aggregate intrinsic value	$ 1,040,000	$ 1,242,000	$ 719,000
unrecognized restricted stock expense	$ 500,000
cost is expected to be recognized over the weighted-average period	2 years 1 month 24 days
Director [Member]
Restricted stock [Line Items]
Deferred shares granted value	$ 40,000
Deferred Compensation, Share-based Payments [Member]
Restricted stock [Line Items]
Deferred shares outstanding	77,293
Restricted Stock [Member]
Restricted stock [Line Items]
Deferred shares outstanding	162,500
vesting period restricted stock	3 years
unrecognized restricted stock expense	$ 600,000
cost is expected to be recognized over the weighted-average period	2 years 3 months