Debt and Credit Facilities (Long-Term Debt Excluding Current Maturities) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Long-term Debt, Excluding Current Maturities	$ 3,977.9	$ 3,788.3
7.20% Debentures Due 2014-2025 [Member]
Debt instrument, interest rate	7.20%	7.20%
Long-term Debt, Excluding Current Maturities	$ 7.5	$ 14.9
3.55% Senior Notes due 2024 [Member]
Debt instrument, interest rate	3.55%	3.55%
6.48% Debentures Due 2025 [Member]
Debt instrument, interest rate	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	3.50%	3.50%
Long-term Debt, Excluding Current Maturities	$ 398.9	$ 398.4
Three Point Seven Five Percent Senior Notes Due Two Thousand Twenty Eight [Member]
Debt instrument, interest rate	3.75%	3.75%
Long-term Debt, Excluding Current Maturities	$ 547.3	$ 546.8
Three Point Eight Percent Senior Notes Due Two Thousand Twenty Nine [Member]
Debt instrument, interest rate	3.80%	3.80%
Long-term Debt, Excluding Current Maturities	$ 746.4	$ 745.8
5.750% Senior Notes Due 2043 [Member]
Debt instrument, interest rate	5.75%	5.75%
Long-term Debt, Excluding Current Maturities	$ 495.4	$ 495.2
4.650% Percent Senior Notes due Twenty Forty Four [Member]
Debt instrument, interest rate	4.65%	4.65%
Long-term Debt, Excluding Current Maturities	$ 296.6	$ 296.4
Four Point Three Percent Senior Notes Due Two Thousand Forty Eight [Member]
Debt instrument, interest rate	4.30%	4.30%
Long-term Debt, Excluding Current Maturities	$ 296.6	$ 296.4
Four Point Five Percent Senior Notes Due Two Thousand Forty Nine [Member]
Debt instrument, interest rate	4.50%	4.50%
Long-term Debt, Excluding Current Maturities	$ 346.2	$ 346.0
Five point Twenty-Five Percent Senior Notes Due Two Thousand Thirty Three
Debt instrument, interest rate	5.25%	5.25%
Long-term Debt, Excluding Current Maturities	$ 693.3	$ 0.0
Three Point Five Five Percent Senior Notes Due Two Thousand Twenty Four
Long-term Debt, Excluding Current Maturities	$ 0.0	$ 498.7