Note 11 - Treasury Stock and Repurchase Program (Details Textual) - USD ($)		1 Months Ended
	Oct. 30, 2018	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Oct. 30, 2018	Jan. 30, 2012	Jan. 31, 2011	Oct. 19, 2018
Treasury Stock, Shares, Acquired		7,523	12,636	3,857
October 2018 Share Repurchase Program [Member]
Stock Repurchase Program, Authorized Amount	$ 2,000,000				$ 2,000,000			$ 2,000,000
Treasury Stock, Shares, Acquired					49,789
Former Repurchase Program [Member]
Treasury Stock, Shares, Acquired						85,219
January 2011 Share Repurchase Program [Member]
Treasury Stock, Shares, Acquired							18,400
September 2012 Share Repurchase Program [Member]
Stock Repurchase Program, Authorized Amount	$ 3,000,000				$ 3,000,000
Treasury Stock, Shares, Acquired	207,047