Derivative Financial instruments and Risk Management- Effect of derivatives designated as hedging instruments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	$ 17	$ (90)	$ 96	$ (98)
Amount of gain (losses) reclassified from AOCI	39	75	(79)	5
Sales and revenues	12,889	9,997	24,776	20,632
Cost of goods sold	8,881	7,113	16,893	14,379
Other income (expense)	201	29	526	251
Designated Derivatives \| Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	17	(90)	96	(98)
Amount of gain (losses) reclassified from AOCI	(39)	(75)	79	(5)
Machinery, Energy & Transportation
Derivative Instruments, Gain (Loss)
Sales and revenues	12,193	9,310	23,384	19,224
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	54	(34)	7	(124)
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Sales
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	(10)	11	(23)	16
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	10	(32)	38	(43)
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	0	(12)	7	(16)
Financial Products
Derivative Instruments, Gain (Loss)
Sales and revenues	696	687	1,392	1,408
Interest Expense	116	149	241	324
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	(38)	(35)	81	66
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	(32)	(43)	80	28
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	0	9	2	20
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	1	(9)	1	(24)
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	(6)	(19)	(16)	(24)
All other excluding Financial Products
Derivative Instruments, Gain (Loss)
Interest Expense	120	135	262	248
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)	$ (1)	$ (2)	$ (2)

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

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