Supplementary Financial Information (Schedule Of Trade Accounts And Other Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Supplementary Financial Information [Abstract]
Gross trade accounts and other receivables	$ 750	$ 767
Allowance for uncollectible accounts	(12)	(7)
Trade accounts receivable - net	$ 738	$ 760

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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