v3.24.1.u1
Debt and Credit Facilities (Long-Term Debt Excluding Current Maturities) (Details) - USD ($)
$ in Millions
Mar. 31, 2024
Dec. 31, 2023
Long-term debt excluding current maturities $ 3,978.7 $ 3,977.9
Seven Point Two Zero Percent Debentures [Domain]    
Debt Instrument, Interest Rate, Stated Percentage 7.20% 7.20%
Long-term debt excluding current maturities $ 7.5 $ 7.5
6.48% Debentures Due 2025 [Member]    
Debt Instrument, Interest Rate, Stated Percentage 6.48% 6.48%
Long-term debt excluding current maturities $ 149.7 $ 149.7
Three Point Five Percent Senior notes Due Two Thousand Twenty Six [Member]    
Debt Instrument, Interest Rate, Stated Percentage 3.50% 3.50%
Long-term debt excluding current maturities $ 399.0 $ 398.9
Three Point Seven Five Percent Senior Notes Due Two Thousand Twenty Eight [Member]    
Debt Instrument, Interest Rate, Stated Percentage 3.75% 3.75%
Long-term debt excluding current maturities $ 547.5 $ 547.3
Three Point Eight Percent Senior Notes Due Two Thousand Twenty Nine [Member]    
Debt Instrument, Interest Rate, Stated Percentage 3.80% 3.80%
Long-term debt excluding current maturities $ 746.6 $ 746.4
5.75% Senior notes due 2043 [Member]    
Debt Instrument, Interest Rate, Stated Percentage 5.75% 5.75%
Long-term debt excluding current maturities $ 495.5 $ 495.4
Four Point Six Five Percent Senior Notes due Twenty Forty Four [Member]    
Debt Instrument, Interest Rate, Stated Percentage 4.65% 4.65%
Long-term debt excluding current maturities $ 296.6 $ 296.6
Four Point Three Percent Senior Notes Due Two Thousand Forty Eight [Member]    
Debt Instrument, Interest Rate, Stated Percentage 4.30% 4.30%
Long-term debt excluding current maturities $ 296.6 $ 296.6
Four Point Five Percent Senior Notes Due Two Thousand Forty Nine [Member]    
Debt Instrument, Interest Rate, Stated Percentage 4.50% 4.50%
Long-term debt excluding current maturities $ 346.2 $ 346.2
Five point Twenty-Five Percent Senior Notes Due Two Thousand Thirty Three    
Debt Instrument, Interest Rate, Stated Percentage 5.25% 5.25%
Long-term debt excluding current maturities $ 693.5 $ 693.3