Equipment held for lease (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	$ 22,474	$ 22,215
Equipment held for lease, accumulated depreciation	(7,873)	(7,150)
Equipment held for lease, net	14,601	15,065
Railcars [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	9,402	9,260
Aircraft [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	8,204	8,093
Other [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment held for lease, gross	$ 4,868	$ 4,862

The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121578510&loc=d3e41551-112718

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=121589968&loc=d3e41460-112716

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- Definition

Amount before accumulated depreciation of physical assets used in the normal conduct of business to produce goods and services subject to or available for lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=121578510&loc=d3e41551-112718

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=121589968&loc=d3e41457-112716

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

+ References

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