Basis of Presentation and Summary of Significant Accounting Policies Narrative (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Dec. 31, 2011 atms
Related Party Transaction [Line Items]
Number of Years for ATM Master Purchase Agreement			5
Banco Bradesco SA [Member]
Related Party Transaction [Line Items]
Target Number of ATMs to be Purchased under Master Purchase Agreement			30,000
Related Party Transaction, Revenues from Transactions with Related Party	$ 40	$ 95
Due from Related Parties	9	9
Misapplication of Accounting Guidance Related To Recognition Of Income Tax Expense
Related Party Transaction [Line Items]
Income tax expense (benefit)	$ 5