Derivative Financial instruments and Risk Management- Effect of derivatives designated as hedging instruments (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	$ 79	$ (8)
Amount of gain (losses) reclassified from AOCI	(118)	(70)
Sales and revenues	11,887	10,635
Cost of goods sold	8,012	7,266
Other income (expense)	325	222
Designated Derivatives \| Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	79	(8)
Amount of gain (losses) reclassified from AOCI	118	70
Machinery, Energy & Transportation
Derivative Instruments, Gain (Loss)
Sales and revenues	11,191	9,914
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	(47)	(90)
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Sales
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	(13)	5
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	28	(11)
Machinery, Energy & Transportation \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	7	(4)
Financial Products
Derivative Instruments, Gain (Loss)
Sales and revenues	696	721
Interest Expense	125	175
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	119	101
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	112	71
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	2	11
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amount of gains (losses) recognized in AOCI	0	(15)
Financial Products \| Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of gain (losses) reclassified from AOCI	(10)	(5)
All other excluding Financial Products
Derivative Instruments, Gain (Loss)
Interest Expense	142	113
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)

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

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