Debt and Credit Facilities (Short-Term Borrowings and Current Maturities of Long-Term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Short-term borrowings and current maturities of long-term debt	$ 650.5	$ 350.6
Debentures With Put Feature [Member]
Short-term borrowings and current maturities of long-term debt	343.0	343.0
Two Point Six Two Five Percent Senior Notes Due Two Thousand Twenty [Member]
Short-term borrowings and current maturities of long-term debt	299.7	0.0
Current Maturities Of Long Term Debt [Member]
Short-term borrowings and current maturities of long-term debt	$ 7.8	$ 7.6