Financial Instruments (Schedule of Short-term and Long-term Classification) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Short-term commercial paper borrowings	$ (1,494.2)	$ (498.9)
Carrying Amount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term debt, including current portion	(13,823.0)	(9,799.7)
Fair Value
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term debt, including current portion	(15,150.0)	(9,989.4)
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term debt, including current portion	0.0	0.0
Significant Other Observable Inputs (Level 2) | Fair Value
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term debt, including current portion	(15,150.0)	(9,989.4)
Significant Unobservable Inputs (Level 3) | Fair Value
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term debt, including current portion	0.0	0.0
Commercial Paper | Carrying Amount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Short-term commercial paper borrowings	(1,494.2)	(498.9)
Commercial Paper | Fair Value
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Short-term commercial paper borrowings	(1,491.6)	(497.6)
Commercial Paper | Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Short-term commercial paper borrowings	0.0	0.0
Commercial Paper | Significant Other Observable Inputs (Level 2) | Fair Value
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Short-term commercial paper borrowings	(1,491.6)	(497.6)
Commercial Paper | Significant Unobservable Inputs (Level 3) | Fair Value
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Short-term commercial paper borrowings	$ 0.0	$ 0.0