XML 32 R40.htm IDEA: XBRL DOCUMENT v3.20.1
Note 6 - Shareholders' Equity (Details Textual) - USD ($)
 1 Months Ended 12 Months Ended
Apr. 30, 1998
Mar. 31, 2020
Mar. 31, 2019
Jan. 21, 2020
Jan. 25, 2019
Jul. 23, 2018
Jan. 22, 2018
May 08, 2017
Nov. 01, 2010
Oct. 31, 2008
Nov. 08, 2006
Preferred Stock, Shares Issued, Total (in shares) 250,000 3,000 3,000                
Preferred Stock, Par or Stated Value Per Share (in dollars per share) $ 0.001 $ 0.001 $ 0.001                
Shares Issued, Price Per Share (in dollars per share) $ 4                    
Payments of Stock Issuance Costs $ 112,187                    
Convertible Preferred Stock, Shares Issued upon Conversion (in shares) 4.05                    
Preferred Stock, Liquidation Preference Per Share (in dollars per share) $ 4 $ 4 $ 4                
Preferred Stock, Shares Outstanding, Ending Balance (in shares)   3,000 3,000                
Stock Repurchase Program, Authorized Amount         $ 30,000,000       $ 20,000,000 $ 20,000,000 $ 20,000,000
Stock Repurchased and Retired During Period, Shares (in shares)   613,000 0                
Stock Repurchased and Retired During Period, Value   $ 11,497,000                  
Stock Repurchase Program, Remaining Authorized Repurchase Amount   $ 28,700,000                  
Dividends Payable, Amount Per Share (in dollars per share)       $ 0.27   $ 0.27 $ 0.25 $ 0.20      
Convertible Preferred Stock [Member]                      
Preferred Stock, Shares Outstanding, Ending Balance (in shares)   2,500 2,500