Financial Instruments (Narrative) (Details) € in Millions, $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($)	Dec. 31, 2015 EUR (€)	Dec. 31, 2014 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Four Quarter Rolling Average Of Notional Amount Of Foreign Exchange Contracts Hedging Foreign Currency Transactions	$ 15,600		$ 13,900
Gain on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	$ 63		$ 53
Notes 1.250% due 2023 [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Debt Instrument, Issuance Date	May 22, 2015	May 22, 2015
Proceeds from Issuance of Debt \| €		€ 750

Date the debt instrument was issued, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Four quarter rolling average notional amount of all foreign currency derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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