Other Assets (Schedule Of Other Assets) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Other Assets [Abstract]
Property, Plant and Equipment, Gross	$ 696	$ 693
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(428)	(411)
Property, Plant and Equipment, Net	268	282
Restricted cash collections for securitization trusts	2,159	2,983
Deferred Tax Assets, State Taxes	1,309	1,190
Derivative Asset, Fair Value, Gross Asset	668	2,298
Restricted cash and cash equivalents	531	889
Cash and securities collateral placed with counterparties	447	1,290
Other accounts receivable	445	525
Cash reserve deposits held for securitization trusts	429	442
Unamortized Debt Issuance Expense	418	425
Nonmarketable equity securities	283	303
Other Assets, Miscellaneous	993	1,281
Other Assets	$ 7,950	$ 11,908