Long-Term Debt - Long-Term Debt (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Total debt	$ 5,041.6	$ 5,040.0
Less: Current maturities	(699.6)	(699.1)
Long-term debt	4,342.0	4,340.9
0.650% Senior Notes, Due 2023 (discharged)
Debt Instrument [Line Items]
Total debt	699.6	699.1
4.250% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	399.1	398.9
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124.7	124.7
3.450% Senior Notes, Due 2027
Debt Instrument [Line Items]
Total debt	298.4	298.3
3.500% Senior Notes, Due 2027
Debt Instrument [Line Items]
Total debt	491.7	491.5
2.500% Senior Notes, Due 2030
Debt Instrument [Line Items]
Total debt	470.8	470.5
2.400% Senior Notes, Due 2031
Debt Instrument [Line Items]
Total debt	888.8	888.6
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	228.4	228.4
4.250% Senior Notes, Due 2047
Debt Instrument [Line Items]
Total debt	590.2	590.2
3.200% Senior Notes, Due 2051
Debt Instrument [Line Items]
Total debt	$ 849.9	$ 849.8

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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

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