Receivables, Allowance for Credit Losses and Credit Quality of Receivables - Components of Accounts and Notes Receivable, Net (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2021	Dec. 31, 2020
Current:
Receivables	$ 697	$ 697	$ 703
Current receivables, net	(81)	(81)	(67)
Long-term:	616	616	636
Receivables
Allowance for credit losses	20	20	20	$ 20
Long-term receivables, net	636	636	656
Financing Receivable, Allowance for Credit Loss, Noncurrent	(5)	(5)	(2)
Financing Receivable, before Allowance for Credit Loss	25	25	$ 22
Allowance for Loan and Lease Losses, Period Increase (Decrease)	$ 12	$ 40

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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