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Note 14 - Earnings and Dividends Per Share - Dividends Declared (Details) - USD ($) $ / shares in Units, $ in Millions | 9 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Dividend per share (in dollars per share) | $ 0.4 |
Dividends paid | $ 187.7 | $ 188.1
O 2025 Q1 Dividends [Member] |  |
Dividend per share (in dollars per share) | $ 0.39 |
Dividends paid | $ 61.5 |
O 2025 Q2 Dividends [Member] |  |
Dividend per share (in dollars per share) | $ 0.4 |
Dividends paid | $ 63.8 |
O 2025 Q3 Dividends [Member] |  |
Dividend per share (in dollars per share) | $ 0.4 |
Dividends paid | $ 62.4 |

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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1 + Details
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- Definition Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-15 + Details
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