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Inventories - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018
Schedule of Inventory [Line Items] |  |  |  |
Inventory write-downs |  |  | $ 649 | $ 572
Inventory write-downs for excess raw materials |  |  |  |
Schedule of Inventory [Line Items] |  |  |  |
Inventory write-downs | $ 500 | $ 410 | $ 547 | $ 440

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- Definition Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116847112&loc=d3e4542-108314 + Details
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- Details
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