Note 8 - Capital Stock - Dividends Declared (Details) - USD ($) $ / shares in Units, $ in Thousands	11 Months Ended		12 Months Ended												153 Months Ended
	Nov. 26, 2025	[1]	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2025
Common Stock, Dividends, Per Share, Declared (in dollars per share)	$ 1.2	[2]	$ 1.44	$ 1.8	$ 2.475	$ 3.9	$ 3.95	$ 4.8	$ 5.35	$ 8.4	$ 8.4	$ 9.6	$ 10.8	$ 6.975	$ 69.09
Dividends	$ 147,192		$ 96,309	$ 81,127	$ 87,906	$ 97,601	$ 53,570	$ 54,421	$ 55,814	$ 70,717	$ 41,388	$ 38,748	$ 22,643	$ 4,662	$ 852,098

[1] On July 9, 2025, the Company declared a dividend of $0.12 per share to be paid on August 28, 2025. The effect of this dividend is included in the table above but is not reflected in the Company’s financial statements as of June 30, 2025.

[2] On October 15, 2025, the Company declared a dividend of $0.12 per share to be paid on November 26, 2025. The effect of this dividend is included in the table above but is not reflected in the Company’s financial statements as of September 30, 2025.