Accounts Receivable (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Accounts Receivable, after Allowance for Credit Loss [Abstract]
Trade customers	$ 926	$ 948
Related parties	5	12
Allowance for credit losses	(15)	(22)
Accounts receivable from trade customers, net	916	938
Federal and state taxes	211	59
Other	33	39
Accounts receivable, net	$ 1,160	$ 1,036

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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