Financing - Components of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Feb. 22, 2019	Dec. 31, 2018	Jun. 20, 2016
Debt Instrument [Line Items]
Long-term debt	$ 6,328.4		$ 3,430.3
Less: Current portion of long-term debt	1,500.0		455.6
Long-term debt, net of current maturities	4,828.4		2,974.7
Commercial Paper
Debt Instrument [Line Items]
Long-term debt	1,100.0
U.S. dollar-denominated commercial paper | Commercial Paper
Debt Instrument [Line Items]
Long-term debt	884.4		390.1
Euro-denominated commercial paper | Commercial Paper
Debt Instrument [Line Items]
Long-term debt	264.1		270.1
Delayed-draw term loan due 2019 | Line of Credit
Debt Instrument [Line Items]
Long-term debt	0.0		400.0
Delayed-draw term loan due 2020 | Line of Credit
Debt Instrument [Line Items]
Long-term debt	1,000.0		0.0
Term loan due 2020 | Line of Credit
Debt Instrument [Line Items]
Long-term debt	500.0		0.0
Yen variable interest rate term loan due 2022 | Line of Credit
Debt Instrument [Line Items]
Long-term debt	127.1		125.7
1.80% senior unsecured notes due 2019 | Senior Notes
Debt Instrument [Line Items]
Long-term debt	0.0		55.6
Interest rate (as a percent)				1.80%
2.35% senior unsecured notes due 2021 | Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 748.2		747.0
Interest rate (as a percent)	2.35%			2.35%
3.15% senior unsecured notes due 2026 | Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 893.0		891.9
Interest rate (as a percent)	3.15%			3.15%
4.30% senior unsecured notes due 2046 | Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 547.0		546.9
Interest rate (as a percent)				4.30%
0.875% senior convertible notes due 2022 | Convertible Debt
Debt Instrument [Line Items]
Long-term debt	1,347.3	$ 1,300.0	0.0
Interest rate (as a percent)		0.875%
Other
Debt Instrument [Line Items]
Long-term debt	$ 17.3		$ 3.0