Segment Information (Details 5) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Reconciliation of restructuring
Consolidated profit before taxes	$ 2,134	$ 289
Restructuring costs	(69)	(752)
Reportable Segments
Reconciliation of restructuring
Consolidated profit before taxes	2,510	1,522
Reportable Segments \| Construction Industries
Reconciliation of restructuring
Consolidated profit before taxes	1,117	634
Reportable Segments \| Resource Industries
Reconciliation of restructuring
Consolidated profit before taxes	378	160
Reportable Segments \| Energy & Transportation
Reconciliation of restructuring
Consolidated profit before taxes	874	545
Reportable Segments \| Financial Products Segment
Reconciliation of restructuring
Consolidated profit before taxes	141	183
All Other operating segments
Reconciliation of restructuring
Consolidated profit before taxes	57	(14)
Business
Reconciliation of restructuring
Consolidated profit before taxes	2,567	1,508
Restructuring costs	(67)	(747)
Consolidated profit before taxes with restructuring costs	2,500	761
Business \| Reportable Segments \| Construction Industries
Reconciliation of restructuring
Consolidated profit before taxes	1,117	634
Restructuring costs	(14)	(667)
Consolidated profit before taxes with restructuring costs	1,103	(33)
Business \| Reportable Segments \| Resource Industries
Reconciliation of restructuring
Consolidated profit before taxes	378	160
Restructuring costs	(44)	(59)
Consolidated profit before taxes with restructuring costs	334	101
Business \| Reportable Segments \| Energy & Transportation
Reconciliation of restructuring
Consolidated profit before taxes	874	545
Restructuring costs	(5)	(14)
Consolidated profit before taxes with restructuring costs	869	531
Business \| Reportable Segments \| Financial Products Segment
Reconciliation of restructuring
Consolidated profit before taxes	141	183
Restructuring costs	0	(1)
Consolidated profit before taxes with restructuring costs	141	182
Business \| All Other operating segments \| All Other
Reconciliation of restructuring
Consolidated profit before taxes	57	(14)
Restructuring costs	(4)	(6)
Consolidated profit before taxes with restructuring costs	$ 53	$ (20)

Sum of operating profit and nonoperating income or expense including restructuring costs before income or loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 5.P.3)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section 50
-Paragraph 1
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-Name Accounting Standards Codification
-Topic 420
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-Section S99
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