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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) shares in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Mar. 31, 2019 | Jun. 27, 2017
Significant Accounting Policies [Line Items] |  |  |  |  |
Maturity period of investments description | three months or less |  |  |  |
Minimum derivative financial instrument's term (months) | 2 months |  |  |  |
Maximum derivative financial instrument's term (months) | 24 months |  |  |  |
Additional inventory reserve charges | $ 49,000,000 | $ 114,000,000 | $ 606,000,000 |  |
Inventory reserves total | $ 644,000,000 | $ 800,000,000 |  |  |
Percentage of inventory reserve | 17.70% | 21.00% |  |  |
Depreciation expense related to property, plant and equipment | $ 349,000,000 | $ 359,000,000 | 370,000,000 |  |
Accumulated depreciation | 2,687,000,000 | 2,559,000,000 |  |  |
Accumulated depreciation for capital leases | 30,000,000 |  |  |  |
Impairment of long-lived assets | 21,000,000 | 10,000,000 | 54,000,000 |  |
Cash payment for acquisition | 280,000,000 | 86,000,000 | 230,000,000 |  |
Net foreign currency transaction gains (losses) | (52,000,000) | (3,000,000) | $ (10,000,000) |  |
Net revenue recognized from performance obligations satisfied in previous periods | 65,000,000 |  |  |  |
Remaining performance obligations | 1,813,000,000 |  |  |  |
Net allowances for doubtful accounts | $ 161,000,000 | $ 187,000,000 |  |  |
Anti-dilutive stock options outstanding | 20 | 12 | 14 |  |
Five Year Unsecured Revolving Credit Facility [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Credit facility, borrowing capacity |  |  |  |  | $ 3,000,000,000
Scenario, Forecast [Member] | Five Year Unsecured Revolving Credit Facility [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Credit facility, borrowing capacity |  |  |  | $ 3,000,000,000 |
Scenario, Forecast [Member] | Minimum [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Lease assets |  |  |  | 500,000,000 |
Lease liabilities |  |  |  | 500,000,000 |
Scenario, Forecast [Member] | Maximum [Member] |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |
Lease assets |  |  |  | 650,000,000 |
Lease liabilities |  |  |  | $ 650,000,000 |

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