Summary of Significant Accounting Policies - Other Balance Sheet Information (Details) - USD ($) $ in Millions |
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Accounting Policies [Abstract] | ||
| Accounts receivable allowance for doubtful accounts | $ 37 | $ 28 |
| Property, plant and equipment accumulated depreciation | 2,652 | 3,013 |
| Intangible assets accumulated amortization | 1,194 | 1,572 |
| Out-of-market contracts accumulated amortization | $ 372 | $ 354 |
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- Definition Accumulated Amortization of Out of Market Contracts No definition available.
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- References No definition available.
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- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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