Segment Information (Details 5) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reconciliation of restructuring
Consolidated profit before taxes	$ 2,135	$ 1,523	$ 6,455	$ 2,971
Restructuring costs	(110)	(90)	(293)	(1,011)
Reportable Segments
Reconciliation of restructuring
Consolidated profit before taxes	2,646	2,041	7,867	5,447
Reportable Segments \| Construction Industries
Reconciliation of restructuring
Consolidated profit before taxes	1,058	884	3,329	2,418
Reportable Segments \| Resource Industries
Reconciliation of restructuring
Consolidated profit before taxes	414	229	1,203	488
Reportable Segments \| Energy & Transportation
Reconciliation of restructuring
Consolidated profit before taxes	973	743	2,859	1,982
Reportable Segments \| Financial Products Segment
Reconciliation of restructuring
Consolidated profit before taxes	201	185	476	559
All Other operating segments
Reconciliation of restructuring
Consolidated profit before taxes	(10)	5	70	(28)
Business
Reconciliation of restructuring
Consolidated profit before taxes	2,636	2,046	7,937	5,419
Restructuring costs	(107)	(115)	(285)	(1,058)
Consolidated profit before taxes with restructuring costs	2,529	1,931	7,652	4,361
Business \| Reportable Segments \| Construction Industries
Reconciliation of restructuring
Consolidated profit before taxes	1,058	884	3,329	2,418
Restructuring costs	(19)	(15)	(62)	(709)
Consolidated profit before taxes with restructuring costs	1,039	869	3,267	1,709
Business \| Reportable Segments \| Resource Industries
Reconciliation of restructuring
Consolidated profit before taxes	414	229	1,203	488
Restructuring costs	(53)	(59)	(149)	(229)
Consolidated profit before taxes with restructuring costs	361	170	1,054	259
Business \| Reportable Segments \| Energy & Transportation
Reconciliation of restructuring
Consolidated profit before taxes	973	743	2,859	1,982
Restructuring costs	(31)	(28)	(60)	(86)
Consolidated profit before taxes with restructuring costs	942	715	2,799	1,896
Business \| Reportable Segments \| Financial Products Segment
Reconciliation of restructuring
Consolidated profit before taxes	201	185	476	559
Restructuring costs	0	0	(1)	(2)
Consolidated profit before taxes with restructuring costs	201	185	475	557
Business \| All Other operating segments \| All Other
Reconciliation of restructuring
Consolidated profit before taxes	(10)	5	70	(28)
Restructuring costs	(4)	(13)	(13)	(32)
Consolidated profit before taxes with restructuring costs	$ (14)	$ (8)	$ 57	$ (60)

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