Note 6 - Stockholders' Equity (Details Textual)	12 Months Ended
	Dec. 31, 2024 $ / shares shares	Dec. 31, 2023 $ / shares shares	Dec. 31, 2022 $ / shares
Capital Units, Authorized (in shares)	245,000,000
Common Stock, Shares Authorized (in shares)	200,000,000
Preferred Stock, Shares Authorized (in shares)	20,000,000
Common Stock, Voting Rights, Votes Per Share	1
Common Stock, Dividends, Per Share, Declared (in dollars per share) | $ / shares	$ 0.32	$ 0.32	$ 0.32
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	3,000,000
Capital Accumulation Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	10,000,000
O 2024 A Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share) | $ / shares	$ 0.32
O 2023 A Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share) | $ / shares		$ 0.32
O 2022 A Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share) | $ / shares			$ 0.32
Class A Common Stock (No Par Value) [Member]
Common Stock, Shares Authorized (in shares)	25,000,000	25,000,000
Common Stock, Voting Rights, Votes Per Share	10
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	1,000,000