Financial Instruments (Summary of Derivative Instruments) (Details) - Contracts designated as cash flow hedging instruments - Foreign Currency Forward Contracts - USD ($) $ in Millions |
Sep. 30, 2017 |
Dec. 31, 2016 |
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| Foreign Currency Forward Contracts - gains (losses) | ||
| Derivative, notional amount | $ 305 | $ 138 |
| Fair Value, Inputs, Level 2 [Member] | ||
| Foreign Currency Forward Contracts - gains (losses) | ||
| Contracts designated as cash flow hedging instruments | $ 6 | $ (2) |
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Fair value as of the balance sheet date of all derivatives designated as foreign currency fair value hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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