Debt (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Short-Term Borrowings [Abstract]
Short-term debt	$ 5.9	$ 3.9
Long-Term Debt [Abstract]
Long-term debt, carrying amount	5,771.8	5,823.0
Unamortized premium (discount), net	(5.2)	(5.1)
Unamortized debt issuance costs	(25.6)	(27.0)
Unamortized deferred gain from settlement of interest rate swaps	13.4	16.4
Long-term debt	5,754.4	5,807.3
Credit Facility [Member]
Credit Facilities [Abstract]
Credit Facilities, maximum borrowing capacity	$ 2,500.0
Credit Facilities, expiration date	Feb. 14, 2025
Credit Facilities, amount outstanding	$ 0.0
Credit Facilities, covenant terms	The Credit Facility contains and,prior to its expiration, the 364 Day Credit Facility contained, a financial covenant that requires us to maintain a Leverage Ratio of consolidated indebtedness to consolidated EBITDA (earnings before interest, taxes, depreciation, amortization and non-cash charges) of no more than 3.5 times for the most recently ended 12-month period. We amended the Credit Facility and the 364 Day Credit Facility in October 2020 to increase the maximum Leverage Ratio to 4.0 times through December 31, 2021 for the Credit Agreement and to 4.0 times through the maturity of the 364 Day Credit Facility.
Credit Facilities, covenant compliance	At March 31, 2021, we were in compliance with these covenants as our Leverage Ratio was 2.8 times.
Commercial Paper [Member]
Credit Facilities [Abstract]
Credit Facilities, current borrowing capacity	$ 2,000.0
Credit Facilities, amount outstanding	0.0
364 Day Credit Facility [Member]
Credit Facilities [Abstract]
Credit Facilities, maximum borrowing capacity	$ 400.0
Credit Facilities, expiration date	Apr. 02, 2021
Credit Facilities, amount outstanding	$ 0.0
Credit Facilities, covenant terms	The Credit Facility contains and,prior to its expiration, the 364 Day Credit Facility contained, a financial covenant that requires us to maintain a Leverage Ratio of consolidated indebtedness to consolidated EBITDA (earnings before interest, taxes, depreciation, amortization and non-cash charges) of no more than 3.5 times for the most recently ended 12-month period. We amended the Credit Facility and the 364 Day Credit Facility in October 2020 to increase the maximum Leverage Ratio to 4.0 times through December 31, 2021 for the Credit Agreement and to 4.0 times through the maturity of the 364 Day Credit Facility.
Credit Facilities, covenant compliance	At March 31, 2021, we were in compliance with these covenants as our Leverage Ratio was 2.8 times.
Uncommitted credit lines [Member]
Credit Facilities [Abstract]
Credit Facilities, current borrowing capacity	$ 1,000.0
Credit Facilities, amount outstanding	0.0
3.625% Senior Notes due 2022
Long-Term Debt [Abstract]
Long-term debt, carrying amount	$ 1,250.0	1,250.0
Long-term debt, interest rate	3.625%
3.65% Senior Notes due 2024
Long-Term Debt [Abstract]
Long-term debt, carrying amount	$ 750.0	750.0
Long-term debt, interest rate	3.65%
3.60% Senior Notes due 2026
Long-Term Debt [Abstract]
Long-term debt, carrying amount	$ 1,400.0	1,400.0
Long-term debt, interest rate	3.60%
€500 Million 0.80% Senior Notes due 2027
Long-Term Debt [Abstract]
Long-term debt, carrying amount	$ 585.9	611.5
Long-term debt, interest rate	0.80%
2.45% Senior Notes due 2030
Long-Term Debt [Abstract]
Long-term debt, carrying amount	$ 600.0	600.0
Long-term debt, interest rate	2.45%
4.20% Senior Notes due 2030
Long-Term Debt [Abstract]
Long-term debt, carrying amount	$ 600.0	600.0
Long-term debt, interest rate	4.20%
€500 Million 1.40% Senior Notes due 2031
Long-Term Debt [Abstract]
Long-term debt, carrying amount	$ 585.9	$ 611.5
Long-term debt, interest rate	1.40%