Financial Instruments (Debt Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Cash and Cash Equivalents	$ 4,604	$ 3,493
Marketable Securities	97,881
Level 2
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	103,944	98,137
Gross Unrealized Gains	867	97
Gross Unrealized Losses	(74)	(1,054)
Fair Value	104,737	97,180
Cash and Cash Equivalents	6,856	5,963
Marketable Securities	97,881	91,217
Level 2 \| Time deposits
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	2,294	2,202
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	2,294	2,202
Cash and Cash Equivalents	2,294	2,202
Marketable Securities	0	0
Level 2 \| Government bonds
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	55,033	53,634
Gross Unrealized Gains	434	71
Gross Unrealized Losses	(30)	(414)
Fair Value	55,437	53,291
Cash and Cash Equivalents	4,518	3,717
Marketable Securities	50,919	49,574
Level 2 \| Corporate debt securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	27,164	25,383
Gross Unrealized Gains	337	15
Gross Unrealized Losses	(3)	(316)
Fair Value	27,498	25,082
Cash and Cash Equivalents	44	44
Marketable Securities	27,454	25,038
Level 2 \| Mortgage-backed and asset-backed securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Adjusted Cost	19,453	16,918
Gross Unrealized Gains	96	11
Gross Unrealized Losses	(41)	(324)
Fair Value	19,508	16,605
Cash and Cash Equivalents	0	0
Marketable Securities	$ 19,508	$ 16,605

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

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- Definition

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

+ References

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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).

+ References

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-Publisher FASB
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-Topic 320
-SubTopic 10
-Section 50
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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-Topic 320
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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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