Receivables, Allowance for Credit Losses and Credit Quality of Receivables - Components of Accounts and Notes Receivable, Net (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Current:
Receivables	$ 700		$ 697
Current receivables, net	(79)		(81)
Long-term:	621		616
Receivables
Allowance for credit losses	20	$ 20	20
Long-term receivables, net	641		636
Financing Receivable, Allowance for Credit Loss, Noncurrent	(5)		(5)
Financing Receivable, before Allowance for Credit Loss	25		$ 25
Allowance for Loan and Lease Losses, Period Increase (Decrease)	$ 28

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 financing receivable, classified as current.

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