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Derivative Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative assets	$ 48.0		$ 48.0		$ 119.4
Fair Value Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Remaining cumulative basis adjustments on discontinued hedge relationship	17.7		$ 17.7		$ 7.1
Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maximum length of future cash flow hedges			9 years 6 months
Accumulated net loss 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			$ 26.4
Reclassification from AOCI			0.2	$ 0.1
Net Investment Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount outstanding	443.6		443.6
Pre-tax gain (loss) recognized in OCI	(3.7)	(17.8)	(3.3)	(36.0)
Cost of sales and revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) from commodity contracts	4.6	(5.5)	2.4	(10.4)
Interest-Rate Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of outstanding contracts	2,830.2		2,830.2
Notional maturities for interest-rate contracts, remainder of 2023	235.8		235.8
Notional maturities for interest-rate contracts 2024	566.0		566.0
Notional maturities for interest-rate contracts 2025	980.2		980.2
Notional maturities for interest-rate contracts 2026	570.8		570.8
Notional maturities for interest-rate contracts 2027	244.3		244.3
Notional maturities for interest-rate contracts 2028	233.1		233.1
Interest-Rate Contracts \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	(35.6)	39.8	(77.9)	59.7
Foreign-exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount outstanding	2,439.7		$ 2,439.7
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	(44.5)	28.7	$ (65.6)	(0.2)
Foreign-exchange contracts \| Truck, Parts and Other \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	(47.1)	28.5	(67.2)	0.1
Commodity Contract
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount outstanding	43.6		$ 43.6
Foreign-exchange contracts maturity period			within one year
Commodity Contract \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	(2.0)	(43.7)	$ 1.9	(7.8)
Commodity Contract \| Truck, Parts and Other \| Derivative Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Pre-tax gain (loss) recognized in OCI	$ (2.0)	$ (43.7)	$ 1.9	$ (7.8)