Note 8 - Capital Stock - Dividends Declared (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | 162 Months Ended | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2026 |
Jun. 30, 2026 |
Mar. 31, 2026 |
Sep. 30, 2025 |
Jun. 30, 2025 |
Mar. 31, 2025 |
Dec. 31, 2026 |
Dec. 31, 2025 |
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 |
Jun. 30, 2026 |
|||||||
| Common Stock, Dividends, Per Share, Declared (in dollars per share) | $ 0.3 | $ 0.3 | $ 0.36 | $ 0.36 | $ 0.36 | $ 0.36 | $ 1.44 | $ 1.44 | $ 1.8 | $ 2.475 | $ 3.9 | $ 3.95 | $ 4.8 | $ 5.35 | $ 8.4 | $ 8.4 | $ 9.6 | $ 10.8 | $ 6.975 | $ 70.39 | |||||||
| Dividends | $ 190,930 | $ 96,309 | $ 81,127 | $ 87,906 | $ 97,601 | $ 53,570 | $ 54,421 | $ 55,814 | $ 70,717 | $ 41,388 | $ 38,748 | $ 22,643 | $ 4,662 | $ 1,103,869 | |||||||||||||
| Forecast [Member] | |||||||||||||||||||||||||||
| Common Stock, Dividends, Per Share, Declared (in dollars per share) | [1],[2],[3] | $ 1.06 | |||||||||||||||||||||||||
| Dividends | [3] | $ 208,033 | |||||||||||||||||||||||||
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