Goodwill and Intangible Assets - Additional Information (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Servicing Fees, Net	$ 38,000,000	$ 81,000,000
Mortgage Servicing Rights [Member]
Servicing Fees, Net	76,000,000	84,000,000
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together, Principal Amount Outstanding	142,300,000,000		144,900,000,000
Principal Amount Outstanding of Loans Serviced For Third Parties	112,000,000,000		113,200,000,000
Loan Principal Amount Outstanding Underlying Mortgage Servicing Rights Sold	$ 324,000,000	$ 570,000,000