Property, plant and equipment and assets held for lease - Narrative (Detail) - Finance and Financial Products [Member] - Assets held for lease [Member] $ in Millions	Dec. 31, 2017 USD ($)
Property, Plant and Equipment [Line Items]
Future minimum lease rentals to be received, 2018	$ 1,103
Future minimum lease rentals to be received, 2019	857
Future minimum lease rentals to be received, 2020	641
Future minimum lease rentals to be received, 2021	439
Future minimum lease rentals to be received, 2022	283
Future minimum lease rentals to be received, thereafter	$ 407

Future rental payments receivable within one year of the balance sheet date under an operating lease.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

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- Definition

Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

+ References

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- Definition

Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

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- Definition

Future rental payments receivable within the third year from the balance sheet date under an operating lease.

+ References

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- Definition

Future rental payments receivable within the second year from the balance sheet date under an operating lease.

+ References

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- Definition

Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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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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