Other Current Assets (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Other Assets [Abstract]
Derivative Asset	$ 599		$ 599		$ 636
Deferred Receivables Consideration	330		330		379
Receivables from Customers	743		743		450
Financing Receivable, after Allowance for Credit Loss	507		507		424
Premiums Receivable, Net	53		53		35
Prepaid Expense, Current	248		248		184
Tax receivables	514		514		379
Other Receivables	311		311		323
Other current assets	210		210		223
Total other current assets	3,515		3,515		3,033
Financing Receivable, Allowance for Credit Loss	3		3		3
Interest on financing receivables	5	$ 6	19	$ 18
Reinsurance Recoverables	$ 81		$ 81		$ 84