Significant Accounting Policies - Extended Warranty Liability (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Jan. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018
Movement in deferred income
Amortization of deferred revenue	$ (10,200)
Current portion		$ 11,165	$ 11,552	$ 11,493
Noncurrent portion		3,445	3,746	$ 3,758
Extended Warranty
Movement in deferred income
Beginning Balance	$ 566	566	531
Revenue deferred for new extended warranty contracts		220	267
Amortization of deferred revenue		(240)	(260)
Other		(13)	28
Ending Balance		533	566
Current portion		271	277
Noncurrent portion		$ 262	$ 289

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.

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- References

No definition available.

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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- Definition

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

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

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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

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