Note 9 - Stock Repurchase Program - Schedule of Stock Purchases (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended													23 Months Ended
	Oct. 31, 2018	[1]	Jul. 31, 2018	[1]	Apr. 30, 2018	[1]	Jan. 31, 2018	[1]	Oct. 31, 2017	Jul. 31, 2017	Apr. 30, 2017	Jan. 31, 2017	[1]	Oct. 31, 2018		Dec. 31, 2016
Approximate Dollar Value of Shares That May Yet Be Purchased Under the Plan or Programs	$ 381		$ 525		$ 531		$ 576		$ 715	$ 718	$ 718	$ 740		$ 381	[1]	$ 750
Number of Shares Purchased (in shares)	480,855		25,277		178,526		536,058		8,607		80,426	49,920		1,359,669
Average Price Paid per Share (in dollars per share)	$ 0.30		$ 0.26		$ 0.25		$ 0.26		$ 0.30		$ 0.27	$ 0.20		$ 0.27
Number of Shares Purchased as Part of Publicly Announced Plans or Programs (in shares)	480,855		25,277		178,526		536,058		8,607		80,426	49,920		1,359,669

[1] These shares of common stock purchased were purchased through private transactions.