Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Banco Bradesco SA [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	$ 3	$ 5	$ 7	$ 6
Banco Bradesco SA [Member]
Related Party Transaction [Line Items]
Due from Related Parties	$ 2		$ 2		$ 18