Servicing Activities (Narrative - Automobile Servicing Activities) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Servicing Activities [Abstract]
Automobile Servicing Fees	$ 16	$ 30	$ 35	$ 60