Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||||
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Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Jan. 01, 2019 |
Dec. 31, 2018 |
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| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||||||
| Accumulated other comprehensive income (loss), net of tax | $ 8 | $ 8 | $ (6) | |||
| Foreign currency translation adjustment, net of tax | 7 | $ (9) | 14 | $ (18) | ||
| Foreign currency translation adjustment, tax | 3 | $ (3) | 5 | $ (6) | ||
| Operating lease right-of-use assets | 442 | 442 | $ 347 | |||
| Operating lease liability | $ 465 | $ 465 | ||||
| Accounting Standards Update 2016-02 | ||||||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | ||||||
| Operating lease right-of-use assets | 347 | |||||
| Operating lease liability | $ 369 | |||||
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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