Deposits Deposits (Schedule of Maturities of Domestic Deposits of One Hundred Thousand or More) (Details) (Domestic Certificates of Deposit and Other Deposits [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Domestic Certificates of Deposit and Other Deposits [Member]
Three months or less	$ 1,208	$ 1,257
Over three months to six months	515	609
Over six months to twelve months	1,085	1,062
Over twelve months	707	618
Total	$ 3,515	$ 3,546