Reconciliations of consolidated profit before taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	$ 863	$ 2,005	$ 3,054	$ 6,447
Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	1,386	2,490	4,479	8,007
All Other operating segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	27	(21)	31	15
Cost Centers
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	9	(9)	18	32
Corporate Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(122)	(167)	(409)	(492)
Timing
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(39)	6	(90)	(118)
Restructuring Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(87)	(20)	(211)	(162)
Inventory/cost of sales
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(7)	25	(25)	24
Postretirement Benefits Expense
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(32)	19	253	4
Stock-Based Compensation Expense [Member]
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(55)	(57)	(169)	(170)
Financing Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(125)	(58)	(324)	(173)
Currency
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(22)	(62)	(230)	(110)
Other Income Expense Methodology Differences
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(72)	(124)	(244)	(374)
Other
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2	(17)	(25)	(36)
Construction Industries | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	585	940	1,743	3,272
Resource Industries | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	167	311	623	1,368
Energy & Transportation | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	492	1,021	1,718	2,745
Financial Products Segment | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	$ 142	$ 218	$ 395	$ 622