Advances and Other Receivables - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchase discount utilized	$ 228
Purchase discount remaining	93
Allowance for credit loss	$ 38
Financial instruments, collection period	39 months
Reserves for Advances and Other Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit loss	$ 21
Allowance for credit loss	21
Purchase Discount
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit loss	$ 17