Revenues and Segment Information, Contract Balances (Details) $ in Millions	6 Months Ended
	Jun. 30, 2020 USD ($)
Receivables from contracts with customers, included in receivables, net
Decrease	$ (4,100)
Contract liabilities, included in accrued expenses
Beginning balance	55
Decrease	(21)
Ending balance	34
Contract Balances (Textual)
Revenue recognized that was included in contract liabilities as of prior year end	52
Receivables from Contracts with Customers [Member]
Receivables from contracts with customers, included in receivables, net
Beginning balance	5,610
Decrease	(3,007)
Ending balance	$ 2,603