Financial Instruments (Debt Securities) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Cash and Cash Equivalents	$ 10,102	$ 4,604
Fair Value	107,880
Level 2
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	106,863	103,944
Gross Unrealized Gains	2,082	867
Gross Unrealized Losses	(42)	(74)
Fair Value	108,903	104,737
Cash and Cash Equivalents	3,290	6,856
Fair Value	105,613	97,881
Level 2 \| Time deposits
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	2,009	2,294
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	2,009	2,294
Cash and Cash Equivalents	2,009	2,294
Fair Value	0	0
Level 2 \| Government bonds
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	59,073	55,033
Gross Unrealized Gains	1,023	434
Gross Unrealized Losses	(9)	(30)
Fair Value	60,087	55,437
Cash and Cash Equivalents	1,264	4,518
Fair Value	58,823	50,919
Level 2 \| Corporate debt securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	28,632	27,164
Gross Unrealized Gains	678	337
Gross Unrealized Losses	(20)	(3)
Fair Value	29,290	27,498
Cash and Cash Equivalents	17	44
Fair Value	29,273	27,454
Level 2 \| Mortgage-backed and asset-backed securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	17,149	19,453
Gross Unrealized Gains	381	96
Gross Unrealized Losses	(13)	(41)
Fair Value	17,517	19,508
Cash and Cash Equivalents	0	0
Fair Value	$ 17,517	$ 19,508

Cash, Cash Equivalents And Available-For-Sale Debt Securities

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Cash, Cash Equivalents And Available-For-Sale Debt Securities, Amortized Cost

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- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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).

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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 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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