Commitments - Extended Warranty Liability (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Movement in deferred income
Amortization of deferred revenue	$ (4,200)
Current portion	14,197		$ 12,833
Noncurrent portion	4,153		$ 4,301
Extended Warranty
Movement in deferred income
Beginning Balance	425	$ 477
Revenue deferred for new extended warranty contracts	18	40
Amortization of deferred revenue	(53)	(57)
Other	(6)	(13)
Ending Balance	383	447
Current portion	199	219
Noncurrent portion	$ 185	$ 228

Increase in contract with customer liability for new contracts.

No definition available.

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- Definition

Increase (decrease) in contract with customer liability for other changes not specified in the taxonomy, including foreign currency translation adjustments.

+ References

No definition available.

+ Details

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- References

No definition available.

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045

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- Definition

Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(5))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable, classified as current.

+ References

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- Definition

Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable, classified as noncurrent.

+ References

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- Details

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