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Derivative Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative assets	$ 102.8		$ 102.8		$ 21.0
Fair Value Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Remaining cumulative basis adjustments on discontinued hedge relationship	7.0		$ 7.0		$ 12.2
Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maximum length of future cash flow hedges			9 years 8 months 12 days
Accumulated net gain on derivative contracts included in accumulated other comprehensive loss expected to be recognized in the Consolidated Statements of Comprehensive Income in the following 12 months, net of tax			$ 13.9
Reclassification from AOCI	(0.8)	$ 0.0	(2.8)	$ 0.2
Net Investment Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount outstanding	553.8		553.8
Pre-tax gain (loss) recognized in OCI	0.3	(3.7)	12.4	(3.3)
Cost of sales and revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
(Loss) gain from commodity contracts	(3.3)	4.6	(5.9)	2.4
Interest-Rate Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of outstanding contracts	3,156.2		3,156.2
Notional maturities for interest-rate contracts, remainder of 2024	253.8		253.8
Notional maturities for interest-rate contracts 2025	1,000.8		1,000.8
Notional maturities for interest-rate contracts 2026	765.6		765.6
Notional maturities for interest-rate contracts 2027	428.3		428.3
Notional maturities for interest-rate contracts 2028	152.6		152.6
Notional maturities for interest-rate contracts 2029	555.1		555.1
Interest-Rate Contracts \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	56.9	(35.6)	81.6	(77.9)
Foreign-exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount outstanding	1,997.8		$ 1,997.8
Foreign-exchange contracts maturity period			within one year
Foreign-exchange contracts \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	35.9	(44.5)	$ 52.1	(65.6)
Foreign-exchange contracts \| Truck, Parts and Other \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	33.5	(47.1)	47.0	(67.2)
Commodity contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount outstanding	23.0		$ 23.0
Foreign-exchange contracts maturity period			within one year
Commodity contracts \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	(8.4)	(2.0)	$ (13.0)	1.9
Commodity contracts \| Truck, Parts and Other \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	$ (8.4)	$ (2.0)	$ (13.0)	$ 1.9