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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Related Party Transaction [Line Items]
Cumulative Effect on Retained Earnings, Net of Tax			$ 39
Banco Bradesco SA [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	$ 5	$ 10	6	$ 28
Banco Bradesco SA [Member]
Related Party Transaction [Line Items]
Due from Related Parties	$ 2		$ 2		$ 10