Long-Term Debt - Long-Term Debt (Detail) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total debt	$ 5,038.6	$ 5,100.9
Less: Current maturities	(698.7)	(0.1)
Long-term debt	4,339.9	5,100.8
0.650% Senior Notes, Due 2023 (discharged)
Debt Instrument [Line Items]
Total debt	698.7	697.4
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Total debt	398.8	398.3
7% Debentures, Due 2025
Debt Instrument [Line Items]
Total debt	124.6	124.6
3.450% Senior Notes, Due 2027
Debt Instrument [Line Items]
Total debt	298.2	297.9
3.500% Senior Notes, Due 2027
Debt Instrument [Line Items]
Total debt	491.4	496.4
2.500% Senior Notes, Due 2030
Debt Instrument [Line Items]
Total debt	470.3	491.1
2.400% Senior Notes, Due 2031
Debt Instrument [Line Items]
Total debt	888.4	891.8
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Total debt	228.4	228.3
4.250% Senior Notes, Due 2047
Debt Instrument [Line Items]
Total debt	590.1	592.1
3.200% Senior Notes, Due 2051
Debt Instrument [Line Items]
Total debt	849.7	882.9
Other Notes
Debt Instrument [Line Items]
Total debt	$ 0.0	$ 0.1

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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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