Hedging Activities (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Amount expected to be reclassified into earnings within the next 12 months		$ 11
Derivative Asset, Notional Amount		16,548	$ 16,104
Foreign Exchange Forward [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Asset, Notional Amount		5,400	7,700
Foreign Exchange Forward [Member] \| Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member]
Derivative Asset, Notional Amount		800	2,100
Foreign Exchange Forward [Member] \| Cash Flow Hedging [Member] \| Not Designated as Hedging Instrument [Member]
Amount reclassified	$ 14
Gross Notional Value, Translated Earnings Contracts [Member]
Derivative Asset, Notional Amount		8,900	12,200
Gross Notional Value, Collar Options [Member]
Derivative Asset, Notional Amount		2,300	2,500
Gross Notional Value, Foreign Exchange Forward [Member]
Derivative Asset, Notional Amount		$ 6,600	$ 9,700

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994

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- Definition

Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from discontinuance of cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959

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