Other Current Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Other Assets [Abstract]
Derivative Asset	$ 660		$ 636
Deferred receivables consideration	430		379
Receivables from Customers	686		450
Financing Receivable, Net	430		424
Premiums Receivable, Net	27		35
Prepaid Expense, Current	263		184
Tax receivables	527		379
Other Receivables	430		323
Other current assets	172		223
Total other current assets	3,625		3,033
Financing Receivable, Allowance for Credit Losses	3		3
Interest on financing receivables	8	$ 7
Asset Impairment Charges	9
Reinsurance Recoverables	$ 82		$ 84