Goodwill (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended						9 Months Ended
	Sep. 30, 2013		Dec. 31, 2012	Sep. 30, 2013 North America [Member]	Dec. 31, 2012 North America [Member]	Dec. 31, 2011 North America [Member]	Sep. 30, 2013 International [Member]
Goodwill [Line Items]
Goodwill	$ 1,156		$ 1,108	$ 1,108	$ 1,108	$ 1,108	$ 48
Goodwill, Acquired During Period	$ 48	[1]					$ 48	[1]

[1] See Note 2 - "Acquisition of Ally Financial Inc. International Operations" for further discussion.