Net Income (Loss) per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016
Earnings Per Share [Abstract]
Net income (loss)	$ 2,524	$ 23,998	$ 5,341	$ 27,745
Weighted average shares outstanding (shares)	15,317	15,128	15,220	15,047
Net effect of dilutive share-based on the treasury stock method using average market price (shares)	166	165	104	139
Totals (shares)	15,483	15,293	15,324	15,186
Net income (loss) per share - basic (usd per share)	$ 0.16	$ 1.59	$ 0.35	$ 1.84
Net income (loss) per share - diluted (usd per share)	$ 0.16	$ 1.57	$ 0.35	$ 1.83