Note 7 - Stock-based Compensation and Equity Transactions - Options Outstanding (Details) - $ / shares	9 Months Ended
	Jul. 31, 2021
Outstanding, shares (in shares)	789,179
Outstanding, weighted average exercise price (in dollars per share)	$ 4.66
Options granted, shares (in shares)	117,000
Options granted, weighted average exercise price (in dollars per share)	$ 6.57
Options exercised, shares (in shares)	(180,528)
Options exercised, weighted average exercise price (in dollars per share)	$ 3.15
Options cancelled, shares (in shares)	(91,793)
Options canceled or expired, weighted average exercise price (in dollars per share)	$ 5.88
Options outstanding, shares (in shares)	633,858
Options outstanding, weighted average exercise price (in dollars per share)	$ 5.26
Options exercisable, shares (in shares)	323,568
Options exercisable, weighted average exercise price (in dollars per share)	$ 5.78
Options vested and expected to vest, shares (in shares)	633,522
Options vested and expected to vest, weighted average exercise price (in dollars per share)	$ 5.27