Receivables, Allowance for Credit Losses and Credit Quality of Receivables - Components of Accounts and Notes Receivable, Net (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019	Sep. 30, 2019
Current:
Receivables	$ 729	$ 729			$ 791
Current receivables, net	(67)	(67)			(36)
Long-term:	662	662			755
Receivables
Allowance for credit losses	24	24		$ 53	53
Long-term receivables, net	686	686			808
Financing Receivable, Allowance for Credit Loss, Noncurrent	(6)	(6)			0
Financing Receivable, before Allowance for Credit Loss	30	30			$ 53
Cumulative Effect of New Accounting Principle in Period of Adoption			$ (6)
Allowance for Loan and Lease Losses, Period Increase (Decrease)	$ 1	$ 41

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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