Financial Information By Business Segment And Geographic Area (Information By Geographic Area, Net Sales Footnotes) (Details) - USD ($) $ in Billions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
United States
Segment Reporting Information [Line Items]
Segment reporting information, unaffiliated revenue	$ 2.5	$ 2.7	$ 3.1

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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration