Advances and Other Receivables - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss	$ 29	$ 44	$ 29	$ 44
Financial instruments collection period			39 months
Advances and other receivables reserve
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit loss	3	13	$ 7	27
Financing receivable, allowance for credit loss	19	27	19	27
Other Credit Losses, Write-off	16		16
Purchase Discount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss	$ 10	$ 17	$ 10	$ 17