Note 17 - Common Stock (Details Textual) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Dividends, Common Stock	$ 3.5	$ 3.4
Common Class A [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 0.24	$ 0.24
Common Class A [Member] | Quarterly Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 0.06
Common Class A [Member] | One Shareholder [Member]
Common Stock, Ownership, Percent	16.70%
Common Class B [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 0.28	$ 0.28
Common Class B [Member] | Quarterly Dividends [Member]
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 0.07