Guarantees (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Product Warranty Liability [Line Items]
Balance as of January 1	$ 1,548	$ 1,449
Warranties and performance guarantees issued	133	137
Settlements made	129	110
Other	(16)	9
Balance as of September 30	$ 1,536	$ 1,485

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

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Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

+ References

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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