Receivables (Schedule of Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Accounts receivable	$ 1,162	$ 1,303
Less: allowance for doubtful accounts	(62)	(65)
Net trade receivables	1,100	1,238
Unbilled receivables	226	181
Miscellaneous receivables	202	183
Receivables, net	$ 1,528	$ 1,602

Amount, after allowance for credit loss, of accounts and financing receivables, classified as current. Includes, but is not limited to, notes and loan receivable.

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

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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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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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