Finance Receivables And Loans, Net (Financing Receivable Credit Quality Indicators) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	$ 96,993	$ 99,055	$ 119,913
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	56,028	53,715
Consumer Loans Auto Financing Receivable [Member] | Performing Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	55,751	53,455
Consumer Loans Auto Financing Receivable [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	277	260
Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	9,270	9,821
Residential Mortgage [Member] | Performing Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	8,846	9,439
Residential Mortgage [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	424	382
First Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	6,774	7,173
First Mortgage [Member] | Performing Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	6,386	6,831
First Mortgage [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	388	342
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	2,496	2,648
Home Equity [Member] | Performing Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	2,460	2,608
Home Equity [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	$ 36	$ 40