Reconciliation of restructuring costs (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reconciliation of restructuring
Consolidated profit before taxes	$ 2,005	$ 2,135	$ 6,447	$ 6,455
Restructuring costs	(24)	(110)	(182)	(293)
Reportable Segments
Reconciliation of restructuring
Consolidated profit before taxes	2,490	2,646	8,007	7,867
Reportable Segments \| Construction Industries
Reconciliation of restructuring
Consolidated profit before taxes	940	1,058	3,272	3,329
Reportable Segments \| Resource Industries
Reconciliation of restructuring
Consolidated profit before taxes	311	414	1,368	1,203
Reportable Segments \| Energy & Transportation
Reconciliation of restructuring
Consolidated profit before taxes	1,021	973	2,745	2,859
Reportable Segments \| Financial Products Segment
Reconciliation of restructuring
Consolidated profit before taxes	218	201	622	476
All Other operating segments
Reconciliation of restructuring
Consolidated profit before taxes	(21)	(10)	15	70
Operating Segments
Reconciliation of restructuring
Consolidated profit before taxes	2,469	2,636	8,022	7,937
Restructuring costs	(20)	(107)	(161)	(285)
Consolidated profit before taxes with restructuring costs	2,449	2,529	7,861	7,652
Operating Segments \| Reportable Segments \| Construction Industries
Reconciliation of restructuring
Consolidated profit before taxes	940	1,058	3,272	3,329
Restructuring costs	0	(19)	(54)	(62)
Consolidated profit before taxes with restructuring costs	940	1,039	3,218	3,267
Operating Segments \| Reportable Segments \| Resource Industries
Reconciliation of restructuring
Consolidated profit before taxes	311	414	1,368	1,203
Restructuring costs	(11)	(53)	(40)	(149)
Consolidated profit before taxes with restructuring costs	300	361	1,328	1,054
Operating Segments \| Reportable Segments \| Energy & Transportation
Reconciliation of restructuring
Consolidated profit before taxes	1,021	973	2,745	2,859
Restructuring costs	(7)	(31)	(59)	(60)
Consolidated profit before taxes with restructuring costs	1,014	942	2,686	2,799
Operating Segments \| Reportable Segments \| Financial Products Segment
Reconciliation of restructuring
Consolidated profit before taxes	218	201	622	476
Restructuring costs	0	0	0	(1)
Consolidated profit before taxes with restructuring costs	218	201	622	475
Operating Segments \| All Other operating segments \| All Other
Reconciliation of restructuring
Consolidated profit before taxes	(21)	(10)	15	70
Restructuring costs	(2)	(4)	(8)	(13)
Consolidated profit before taxes with restructuring costs	$ (23)	$ (14)	$ 7	$ 57

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.

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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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