Debt - Summary of Debt (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Commercial paper	$ 324.9	$ 0.0
Other debt	18.9	48.4
Debt
Total debt	6,325.6	7,015.0
Short-term debt and current portion of long-term debt	(633.9)	(318.7)
Long-term debt	5,691.7	6,696.3
2.60% senior notes due 2019
Debt Instrument [Line Items]
Senior notes	0.0	267.3
4.70% senior notes due 2020
Debt Instrument [Line Items]
Senior notes	304.8	304.6
3.15% senior notes due 2021
Debt Instrument [Line Items]
Senior notes	93.6	97.5
3.75% senior notes due 2021
Debt Instrument [Line Items]
Senior notes	333.3	353.2
4.00% senior notes due 2022
Debt Instrument [Line Items]
Senior notes	249.2	249.0
3.85% senior notes due 2023
Debt Instrument [Line Items]
Senior notes	1,387.1	1,740.8
5.00% senior notes due 2023
Debt Instrument [Line Items]
Senior notes	308.4	310.0
4.00% senior notes due 2024
Debt Instrument [Line Items]
Senior notes	199.4	496.4
3.90% senior notes due 2025
Debt Instrument [Line Items]
Senior notes	46.8	90.3
4.20% senior notes due 2026
Debt Instrument [Line Items]
Senior notes	1,985.9	1,984.5
5.375% senior notes due 2036
Debt Instrument [Line Items]
Senior notes	416.0	415.8
5.50% senior notes due 2046
Debt Instrument [Line Items]
Senior notes	$ 657.3	$ 657.2

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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