Accounts Receivable, Net (Allowance for Credit Loss) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivable, Allowance for Credit Loss	$ (389)
Current period provision for expected credit losses1	(63)
Write-offs charged against the allowance for expected credit losses	5
Other2	(50)
Accounts Receivable, Allowance for Credit Loss	(497)
ASU 2016-13 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other2	64
COVID-19 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current period provision for expected credit losses1	$ 38