Note 1 - Description of Business and Significant Accounting Policies (Details Textual)	Mar. 31, 2024 $ / shares shares	Dec. 31, 2023 $ / shares shares	Mar. 31, 2023 shares
Number of Wholly-Owned Operating Subsidiaries	4
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares	$ 0.1	$ 0.1
Common Stock, Shares Authorized (in shares)	20,000,000	20,000,000
Common Stock, Shares, Outstanding (in shares)	7,748,922	7,748,922	7,746,922
Common Stock, Shares, Issued (in shares)	7,748,922	7,748,922