Equipment held for lease (Detail) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	$ 30,496	$ 30,024
Equipment held for lease, accumulated depreciation	(12,512)	(12,196)
Equipment held for lease, net	17,984	17,828
Railcars [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	10,195	10,137
Aircraft [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	14,635	14,201
Other [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	$ 5,666	$ 5,686

Amount of accumulated depreciation of lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 840
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481501/840-20-50-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479773/842-30-50-13

Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-SubTopic 20
-Topic 840
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481532/840-20-45-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-1

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant