Accounts and Notes Receivable Allowance Rollforward (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($)
Receivables [Abstract]
Accounts Receivable, Allowance for Credit Loss, Beginning Balance	$ 174
Additions charged to expenses	153
Write-offs charged against allowance	(6)
Recoveries collected	(99)
Other deductions against allowance	(12)
Accounts Receivable, Allowance for Credit Loss, Ending Balance	$ 210