Long-Term Debt - Long-Term Debt (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total debt	$ 3,263.8	$ 2,773.6
Less: Current maturities of long-term debt and short-term facilities	(639.9)	(340.0)
Long-term debt	2,623.9	2,433.6
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	397.2	397.0
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124.4	124.4
3.450% Senior Notes, Due 2027
Debt Instrument [Line Items]
Total debt	297.3	297.3
3.500% Senior Notes, Due 2027
Debt Instrument [Line Items]
Total debt	495.4	495.3
2.500% Senior Notes, Due 2030
Debt Instrument [Line Items]
Total debt	489.5
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	228.2	228.1
4.250% Senior Notes, Due 2047
Debt Instrument [Line Items]
Total debt	591.7	591.7
Floating Rate Senior Notes, Due 2020
Debt Instrument [Line Items]
Total debt	299.9	299.7
Other Notes
Debt Instrument [Line Items]
Total debt	0.2	0.1
Trade Receivable Facility
Debt Instrument [Line Items]
Total debt	$ 340.0	$ 340.0

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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