Supplementary Financial Information (Schedule Of Trade Accounts Receivable) (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Supplementary Financial Information [Abstract]
Gross trade accounts and other receivables	$ 573	$ 528
Trade accounts and other receivables from affiliates	(138)	(118)
Allowance for uncollectible accounts	(5)	(3)
Trade accounts receivable from nonaffiliates - net	$ 430	$ 407

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

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- Definition

Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due within 1 year (or 1 business cycle).

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