Reconciliations of consolidated profit before taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	$ 2,005	$ 2,135	$ 6,447	$ 6,455
Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,490	2,646	8,007	7,867
All Other operating segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(21)	(10)	15	70
Cost Centers
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(9)	29	32	55
Corporate Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(167)	(134)	(492)	(480)
Timing
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	6	(18)	(118)	(168)
Restructuring Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(20)	(110)	(162)	(293)
Inventory/cost of sales
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	25	(20)	24	3
Postretirement Benefits Expense
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	19	58	4	227
Stock-Based Compensation Expense [Member]
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(57)	(52)	(170)	(164)
Financing Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(58)	(56)	(173)	(203)
Currency
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(62)	(96)	(110)	(145)
Other Income Expense Methodology Differences
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(124)	(88)	(374)	(261)
Other
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(17)	(14)	(36)	(53)
Operating Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,469	2,636	8,022	7,937
Machinery, Energy & Transportation | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,272	2,445	7,385	7,391
Machinery, Energy & Transportation | Operating Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	1,758	1,945	5,832	5,992
Machinery, Energy & Transportation | Operating Segments | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,272	2,445	7,385	7,391
Machinery, Energy & Transportation | Operating Segments | All Other operating segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(21)	(10)	15	70
Machinery, Energy & Transportation | Operating Segments | Cost Centers
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(9)	29	32	55
Machinery, Energy & Transportation | Operating Segments | Corporate Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(168)	(134)	(487)	(480)
Machinery, Energy & Transportation | Operating Segments | Timing
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	6	(18)	(118)	(168)
Machinery, Energy & Transportation | Operating Segments | Restructuring Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(20)	(96)	(131)	(278)
Machinery, Energy & Transportation | Operating Segments | Inventory/cost of sales
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	25	(20)	24	3
Machinery, Energy & Transportation | Operating Segments | Postretirement Benefits Expense
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	19	58	4	227
Machinery, Energy & Transportation | Operating Segments | Stock-Based Compensation Expense [Member]
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(55)	(50)	(164)	(158)
Machinery, Energy & Transportation | Operating Segments | Financing Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(58)	(56)	(173)	(203)
Machinery, Energy & Transportation | Operating Segments | Currency
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(62)	(96)	(110)	(145)
Machinery, Energy & Transportation | Operating Segments | Other Income Expense Methodology Differences
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(124)	(88)	(374)	(261)
Machinery, Energy & Transportation | Operating Segments | Other
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(47)	(19)	(71)	(61)
Financial Products | Operating Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	247	190	615	463
Financial Products | Operating Segments | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	218	201	622	476
Financial Products | Operating Segments | All Other operating segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Operating Segments | Cost Centers
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Operating Segments | Corporate Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	1	0	(5)	0
Financial Products | Operating Segments | Timing
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Operating Segments | Restructuring Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	(14)	(31)	(15)
Financial Products | Operating Segments | Inventory/cost of sales
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Operating Segments | Postretirement Benefits Expense
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Operating Segments | Stock-Based Compensation Expense [Member]
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(2)	(2)	(6)	(6)
Financial Products | Operating Segments | Financing Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Operating Segments | Currency
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Operating Segments | Other Income Expense Methodology Differences
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Operating Segments | Other
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	$ 30	$ 5	$ 35	$ 8