Tax Effects of Temporary Differences Representing Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Assets:
Accrued liabilities	$ 308.2	$ 314.3
R&D expense capitalization	365.8	257.1
Net operating loss and tax credit carryforwards	110.3	144.8
Inventory adjustments	62.9	64.6
Allowance for losses on receivables	50.6	53.2
Other	127.5	132.2
Deferred Tax Assets, Gross, Total	1,025.3	966.2
Valuation allowance	(1.6)	(2.3)
Deferred Tax Assets, Net of Valuation Allowance, Total	1,023.7	963.9
Liabilities:
Financial Services leasing depreciation	(559.5)	(572.6)
Depreciation and amortization	(231.5)	(219.7)
Postretirement benefit plans	(210.3)	(144.5)
Other	(98.7)	(58.9)
Deferred Tax Liability, Total	(1,100.0)	(995.7)
Net deferred tax liability	$ (76.3)	$ (31.8)