Note 6 - Debt - Short-term and Long-term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Debt, Current	$ 257.7	$ 1,508.9
Finance lease liabilities, current	8.3	8.9
Short-term debt and current portion of long-term debt	257.7	1,508.9
Finance lease liabilities, noncurrent	9.8	14.7
Syndicated revolving credit facility debt issuance costs	(1.6)	(1.8)
Long-term debt	4,215.8	3,228.3
Total debt	4,473.5	4,737.2
Revolving Credit Facility [Member]
Debt, Current	0.0	0.0
Short-term debt and current portion of long-term debt	0.0	0.0
The February 18, 2026 Term Loan Agreement [Member]
Debt, Current	249.4	0.0
Short-term debt and current portion of long-term debt	249.4	0.0
The 4.500% Senior Notes Due in 2030 [Member]
Debt, Current	0.0	750.0
Short-term debt and current portion of long-term debt	0.0	750.0
The 5.125% Senior Note Due in 2036 [Member]
Debt, Current	0.0	750.0
Short-term debt and current portion of long-term debt	0.0	750.0
The 4.125% Senior Notes Due in 2029 [Member]
Long-term debt	604.1	604.8
The 4.450% Senior Notes Due in 2031 [Member]
Long-term debt	496.0	0.0
The 5.750% Senior Notes Due in 2033 [Member]
Long-term debt	493.5	493.0
The 5.250% Senior Notes Due in 2034 [Member]
Long-term debt	588.0	587.3
The 5.250% Senior Notes Due in 2035 [Member]
Long-term debt	693.1	692.7
The 5.125% Senior Notes Due in 2036 [Member]
Long-term debt	495.0	0.0
The 5.500% Senior Notes Due in 2045 [Member]
Long-term debt	346.6	346.5
The 3.625% Senior Notes Due in 2050 [Member]
Long-term debt	$ 491.3	$ 491.1

Amount of debt and lease obligation, classified as current.

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