Note 7 - Shareholders' Equity (Details Textual) - USD ($)	Mar. 31, 2024	Mar. 31, 2023
Common Stock, Shares Authorized (in shares)	75,000,000	75,000,000
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.01	$ 0.01
Common Stock, Shares, Outstanding (in shares)	21,042,652	21,042,652
Treasury Stock, Common, Shares (in shares)	31,923,145	31,923,145
Preferred Stock, Shares Issued (in shares)	3,677	3,677
Preferred Stock, Liquidation Preference, Value	$ 3,677,000,000	$ 3,677,000,000
Series A Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)	3,677
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 1
Preferred Stock, Liquidation Preference, Value	$ 3,677,000