Segment Information (Details 4) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	$ 2,186	$ 1,159	$ 4,320	$ 1,448
Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,711	1,884	5,221	3,406
All Other operating segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	23	(19)	80	(33)
Cost Centers
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(1)	(11)	26	(4)
Corporate Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(178)	(174)	(346)	(289)
Timing
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(66)	(69)	(150)	(107)
Restructuring Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(114)	(169)	(183)	(921)
Inventory/cost of sales
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	31	(8)	23	(76)
Postretirement Benefits Expense
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	82	44	169	91
Stock-Based Compensation Expense [Member]
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(62)	(68)	(112)	(117)
Financing Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(69)	(123)	(147)	(253)
Currency
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(52)	(119)	(49)	(158)
Other Income Expense Methodology Differences
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(95)	21	(173)	(34)
Other
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(24)	(30)	(39)	(57)
Business
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,734	1,865	5,301	3,373
Machinery, Energy & Transportation | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,577	1,693	4,946	3,032
Machinery, Energy & Transportation | Business
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,050	971	4,047	1,076
Machinery, Energy & Transportation | Business | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	2,577	1,693	4,946	3,032
Machinery, Energy & Transportation | Business | All Other operating segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	23	(19)	80	(33)
Machinery, Energy & Transportation | Business | Cost Centers
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(1)	(11)	26	(4)
Machinery, Energy & Transportation | Business | Corporate Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(178)	(174)	(346)	(289)
Machinery, Energy & Transportation | Business | Timing
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(66)	(69)	(150)	(107)
Machinery, Energy & Transportation | Business | Restructuring Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(113)	(169)	(182)	(920)
Machinery, Energy & Transportation | Business | Inventory/cost of sales
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	31	(8)	23	(76)
Machinery, Energy & Transportation | Business | Postretirement Benefits Expense
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	82	44	169	91
Machinery, Energy & Transportation | Business | Stock-Based Compensation Expense [Member]
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(60)	(65)	(108)	(112)
Machinery, Energy & Transportation | Business | Financing Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(69)	(123)	(147)	(253)
Machinery, Energy & Transportation | Business | Currency
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(52)	(119)	(49)	(158)
Machinery, Energy & Transportation | Business | Other Income Expense Methodology Differences
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(95)	21	(173)	(34)
Machinery, Energy & Transportation | Business | Other
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(29)	(30)	(42)	(61)
Financial Products | Business
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	136	188	273	372
Financial Products | Business | Reportable Segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	134	191	275	374
Financial Products | Business | All Other operating segments
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Cost Centers
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Corporate Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Timing
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Restructuring Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(1)	0	(1)	(1)
Financial Products | Business | Inventory/cost of sales
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Postretirement Benefits Expense
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Stock-Based Compensation Expense [Member]
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	(2)	(3)	(4)	(5)
Financial Products | Business | Financing Costs
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Currency
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Other Income Expense Methodology Differences
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	0	0	0	0
Financial Products | Business | Other
Reconciliation of Consolidated profit (loss) before taxes
Consolidated profit before taxes	$ 5	$ 0	$ 3	$ 4