Financial Assets & Liabilities - Fair Value Measurements (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Financial assets and financial liabilities measured at fair value on a recurring basis:
Debt securities - current	$ 2,063	$ 696
Potential reduction in net position of total derivative assets	220	194
Potential reduction in net position of total derivative liabilities	220	194
Recurring
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	8,712	4,819
Total assets	11,104	5,823
Total liabilities	491	673
Recurring \| Prepaid expenses and other current assets
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivative assets	195	149
Recurring \| Investments and sundry assets
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivative assets	112	94
Recurring \| Other accrued expenses and liabilities
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivative liabilities	289	167
Recurring \| Other liabilities
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivative liabilities	202	506
Recurring \| Level 1
Financial assets and financial liabilities measured at fair value on a recurring basis:
Equity investments	0	0
Recurring \| Level 1 \| Money market funds
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	926	427
Recurring \| Level 2
Financial assets and financial liabilities measured at fair value on a recurring basis:
Debt securities - current	2,063	696
Debt securities - noncurrent	22	65
Recurring \| Level 2 \| Interest rate contracts
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivatives designated as hedging - Assets	126	56
Recurring \| Level 2 \| Foreign exchange contracts
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivatives designated as hedging - Assets	161	175
Derivatives designated as hedging - Liabilities	468	635
Derivatives not designated as hedging - Assets	8	10
Derivatives not designated as hedging - Liabilities	18	33
Recurring \| Level 2 \| Time deposits and certificates of deposit
Financial assets and financial liabilities measured at fair value on a recurring basis:
Cash equivalents	7,785	4,392
Recurring \| Level 1 And 2 \| Equity contracts
Financial assets and financial liabilities measured at fair value on a recurring basis:
Derivatives not designated as hedging - Assets	11	1
Derivatives not designated as hedging - Liabilities	$ 4	$ 4
Maximum \| Debt \| Investments and sundry assets
Financial assets and financial liabilities measured at fair value on a recurring basis:
Term of debt instrument	2 years

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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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 noncurrent.

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value, before effects of master netting arrangements, of a 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. Includes assets not subject to a master netting arrangement and elected not to be offset.

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

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Fair value, before effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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Fair value of financial liability or 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 liabilities.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Fair value of financial and nonfinancial obligations.

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