Finance Receivables And Loans, Net (Schedule Of Pass And Criticized Credit Quality Indicators Of Finance Receivables) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	$ 95,281	$ 99,055	$ 121,259
Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	30,059	35,519
Commercial And Industrial Automobile [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	25,691	30,270
Commercial And Industrial Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	0	0
Commercial And Industrial Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	1,607	2,697
Commercial Real Estate Automobile [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	2,761	2,552
Commercial Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	0	0
Pass [Member] | Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	28,434	33,835
Pass [Member] | Commercial And Industrial Automobile [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	24,446	28,978
Pass [Member] | Commercial And Industrial Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	0	0
Pass [Member] | Commercial And Industrial Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	1,312	2,417
Pass [Member] | Commercial Real Estate Automobile [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	2,676	2,440
Pass [Member] | Commercial Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	0	0
Criticized Member | Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	1,625	1,684
Criticized Member | Commercial And Industrial Automobile [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	1,245	1,292
Criticized Member | Commercial And Industrial Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	0	0
Criticized Member | Commercial And Industrial Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	295	280
Criticized Member | Commercial Real Estate Automobile [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	85	112
Criticized Member | Commercial Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	$ 0	$ 0