Note 9 - Stockholders' Equity (Details Textual) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Feb. 28, 2025	Oct. 31, 2023
Dividends Payable, Current	$ 76.0	$ 59.8
Accrued Dividend Equivalents	$ 9.4	$ 5.8
Stock Repurchased and Retired During Period, Shares (in shares)	8,000	1,000,000	7,000
Payments for Repurchase of Common Stock	$ 6.6	$ 636.2	$ 3.7
Maximum [Member]
Share Repurchase Program, Authorized, Amount				$ 500.0	$ 640.0

Amount of dividend equivalents accrued during the period.

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Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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The cash outflow to reacquire common stock during the period.

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Number of shares that have been repurchased and retired during the period.

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