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Inventories - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Inventory [Line Items]
Inventories classified in Other assets	$ 2,175	$ 2,197
Inventories Not Expected to be Sold Within One Year
Inventory [Line Items]
Inventories classified in Other assets	1,800	1,900
Inventories Produced in Preparation for Product Launches
Inventory [Line Items]
Inventories classified in Other assets	$ 387	$ 279

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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.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

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