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Inventories - Narrative (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Inventory [Line Items] |  |
LIFO Inventory Amount | $ 2,200 | $ 2,300
Inventories classified in other assets | 1,187 | 1,117
Inventory Not Expected to be Sold Within One Year |  |
Inventory [Line Items] |  |
Inventories classified in other assets | 1,100 | 1,000
Inventories Produced in Preparation for Product Launches |  |
Inventory [Line Items] |  |
Inventories classified in other assets | $ 80 | $ 80

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- Definition Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(d)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766 + Details
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