Intangible assets and goodwill (Details 2) - USD ($) $ in Millions		12 Months Ended
Jan. 01, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Carrying amount of goodwill by reportable segment
Goodwill acquired		$ 133	$ 7
Goodwill reclassified to held for sale and/or divested			15
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	$ 7,217	7,296	7,558
Impairments, beginning of year	(602)	(602)	(602)
Goodwill acquired		133	7
Held for Sale and Business Divestitures		0	(15)
Impairment Loss		0	0	$ 0
Other Adjustments		(212)	(254)
Goodwill, end of year		7,217	7,296	7,558
Impairments, end of year		(602)	(602)	(602)
Net Goodwill, end of year		6,615	6,694	6,956
Rail Product Solutions Inc.
Carrying amount of goodwill by reportable segment
Goodwill acquired		53
Changes in carrying amount of goodwill by reportable segment:
Goodwill acquired		53
RDS Manufacturing Inc.
Carrying amount of goodwill by reportable segment
Goodwill acquired		59
Changes in carrying amount of goodwill by reportable segment:
Goodwill acquired		59
Net Goodwill, end of year		59
Johan Walter Berg AB
Carrying amount of goodwill by reportable segment
Goodwill acquired				106
Goodwill, Purchase Accounting Adjustments			7
Changes in carrying amount of goodwill by reportable segment:
Goodwill acquired				106
Construction Industries
Carrying amount of goodwill by reportable segment
Goodwill acquired		0	0
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	285	297	313
Impairments, beginning of year	(22)	(22)	(22)
Goodwill acquired		0	0
Held for Sale and Business Divestitures		0	0
Impairment Loss		0	0
Other Adjustments		(12)	(16)
Goodwill, end of year		285	297	313
Impairments, end of year		(22)	(22)	(22)
Net Goodwill, end of year		263	275	291
Resource Industries
Carrying amount of goodwill by reportable segment
Goodwill acquired		0	0
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	4,145	4,287	4,468
Impairments, beginning of year	(580)	(580)	(580)
Goodwill acquired		0	0
Held for Sale and Business Divestitures		0	(15)
Impairment Loss		0	0
Other Adjustments		(142)	(166)
Goodwill, end of year		4,145	4,287	4,468
Impairments, end of year		(580)	(580)	(580)
Net Goodwill, end of year		3,565	3,707	3,888
Energy & Transportation
Carrying amount of goodwill by reportable segment
Goodwill acquired		133	7
Goodwill reassigned	118
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	2,738	2,660	2,718
Goodwill acquired		133	7
Held for Sale and Business Divestitures		0	0
Impairment Loss		0	0
Other Adjustments		(55)	(65)
Goodwill, end of year		2,738	2,660	2,718
Net Goodwill, end of year		2,738	2,660
All Other
Carrying amount of goodwill by reportable segment
Goodwill acquired		0	0
Changes in carrying amount of goodwill by reportable segment:
Goodwill, beginning of year	$ 49	52	59
Goodwill acquired		0	0
Held for Sale and Business Divestitures		0	0
Impairment Loss		0	0
Other Adjustments		(3)	(7)
Goodwill, end of year		$ 49	$ 52	$ 59

Amount of goodwill classified to held for sale and/or divested in the reporting period.

No definition available.

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Represents the amount of goodwill held for sale apart from normal operations and anticipated to be sold in less than one year, as well as the write-off of the carrying amount of goodwill associated with all or a portion of a reporting unit that is sold in the period.

+ References

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of transfers of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized among segments.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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