Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Commitment and Contingencies [Line Items]
Rent expense	$ 5
Operating lease payments for the remainder of 2019	20
2020	26
2021	26
2022	24
2023	19
Thereafter	$ 46
Weighted average discount rate	4.80%
Weighted average remaining lease term	6 years 7 months 6 days
Estimate of possible loss	$ 66
Loss accrual	23
Indirect tax contingency	13
Parent Company [Member] | Euro Medium Term Notes [Member] | Senior Notes [Member]
Commitment and Contingencies [Line Items]
Debt instrument, face amount	1,100	$ 1,100
Other Assets [Member]
Commitment and Contingencies [Line Items]
Operating lease right-of-use assets	123
Other Liabilities [Member]
Commitment and Contingencies [Line Items]
Operating lease liabilities	$ 138