Segment information (Details 4) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information
Consolidated profit before taxes	$ 4,082	$ 139	$ 3,439
Restructuring costs	(1,256)	(1,019)	(898)
Reportable segments
Segment Reporting Information
Consolidated profit before taxes	7,623	3,527	6,065
Reportable segments \| Construction Industries
Segment Reporting Information
Consolidated profit before taxes	3,258	1,650	1,865
Reportable segments \| Resource Industries
Segment Reporting Information
Consolidated profit before taxes	690	(1,047)	1
Reportable segments \| Energy & Transportation
Segment Reporting Information
Consolidated profit before taxes	2,883	2,222	3,390
Reportable segments \| Financial Products Segment
Segment Reporting Information
Consolidated profit before taxes	792	702	809
All Other operating segments
Segment Reporting Information
Consolidated profit before taxes	(43)	(77)	(75)
Business
Segment Reporting Information
Consolidated profit before taxes	7,580	3,450	5,990
Restructuring costs	(1,152)	(879)	(683)
Consolidated profit before taxes with restructuring costs	6,428	2,571	5,307
Business \| Reportable segments \| Construction Industries
Segment Reporting Information
Consolidated profit before taxes	3,258	1,650	1,865
Restructuring costs	(719)	(41)	(123)
Consolidated profit before taxes with restructuring costs	2,539	1,609	1,742
Business \| Reportable segments \| Resource Industries
Segment Reporting Information
Consolidated profit before taxes	690	(1,047)	1
Restructuring costs	(276)	(540)	(305)
Consolidated profit before taxes with restructuring costs	414	(1,587)	(304)
Business \| Reportable segments \| Energy & Transportation
Segment Reporting Information
Consolidated profit before taxes	2,883	2,222	3,390
Restructuring costs	(115)	(248)	(109)
Consolidated profit before taxes with restructuring costs	2,768	1,974	3,281
Business \| Reportable segments \| Financial Products Segment
Segment Reporting Information
Consolidated profit before taxes	792	702	809
Restructuring costs	(3)	(5)	(17)
Consolidated profit before taxes with restructuring costs	789	697	792
Business \| All Other operating segments \| All Other
Segment Reporting Information
Consolidated profit before taxes	(43)	(77)	(75)
Restructuring costs	(39)	(45)	(129)
Consolidated profit before taxes with restructuring costs	$ (82)	$ (122)	$ (204)

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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