Derivative Financial instruments and Risk Management- Effect of derivatives designated as hedging instruments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Derivative Instruments, Gain (Loss)
Sales of Machinery, Energy & Transportation	$ 9,881	$ 12,758	$ 30,513	$ 40,656
Cost of goods sold	6,919	8,569	21,298	27,513
Other income (expense)	14	88	265	316
Designated Derivatives \| Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	5	75	(93)	68
Amount of gain (losses) reclassified from AOCI	(93)	96	(98)	109
Machinery, Energy & Transportation
Derivative Instruments, Gain (Loss)
Sales of Machinery, Energy & Transportation	9,228	11,974	28,452	38,369
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	66	(13)	(58)	8
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Sales
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	(6)	3	10	4
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Cost of Sales
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	(15)		(58)	(4)
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	2		(14)	0
Financial Products
Derivative Instruments, Gain (Loss)
Sales of Machinery, Energy & Transportation	653	784	2,061	2,287
Interest Expense	137	189	461	571
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	(64)	100	2	132
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Other Nonoperating Income (Expense)
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	(63)	89	(35)	91
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	8	9	28	23
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	1	(12)	(23)	(72)
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	(16)	(3)	(40)	(2)
All other excluding Financial Products
Derivative Instruments, Gain (Loss)
Interest Expense	136	103	384	309
All other excluding Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	$ (1)	$ (2)	$ (3)	$ (3)

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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