Financial Instruments - Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Financial assets and financial liabilities measured at fair value on a recurring basis:
Debt securities - current	$ 874	$ 618
Derivative assets	419	731
Derivative liabilities	589	383
Potential reduction in net position of total derivative assets	262	267
Recurring
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	25,096	7,704
Equity investments	1	0
Debt securities - current	873	618
Derivative assets	419	731
Total assets	26,390	9,053
Derivative liabilities	589	383
Recurring \| Prepaid expenses and other current assets
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivative assets	204	385
Recurring \| Investments and sundry assets
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivative assets	215	347
Recurring \| Other accrued expenses and liabilities
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivative liabilities	212	177
Recurring \| Other liabilities
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivative liabilities	377	206
Recurring \| Time deposits and certificates of deposit
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	19,095	7,679
Recurring \| Money market funds
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	6,001	25
Recurring \| Level 1
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	6,001	25
Equity investments	0	0
Derivative assets	4	1
Total assets	6,005	26
Derivative liabilities		40
Recurring \| Level 1 \| Money market funds
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	6,001	25
Recurring \| Level 2
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	19,095	7,679
Equity investments	1
Debt securities - current	873	618
Derivative assets	415	731
Total assets	20,384	9,028
Derivative liabilities	589	343
Recurring \| Level 2 \| Time deposits and certificates of deposit
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	$ 19,095	$ 7,679

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset, deducted from derivative assets.

+ References

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Publisher FASB
-Name Accounting Standards Codification
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