Accounts Receivable (Schedule Of Accounts Receivable) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Trade customers	$ 948	$ 969
Related Party	12	6
Allowance for doubtful accounts	(22)	(23)
Accounts Receivable from trade customers, net	938	952
Federal and state taxes	59	57
Other	39	28
Accounts receivable, net	$ 1,036	$ 1,037

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

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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.

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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