Finance Receivables And Loans, Net (Schedule Of Pass And Criticized Credit Quality Indicators Of Finance Receivables) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	$ 107,991	$ 99,948
Commercial Portfolio Segment [Member] | Commercial Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	34,611	35,904
Commercial Portfolio Segment [Member] | Commercial Loan [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	32,435	33,674
Commercial Portfolio Segment [Member] | Commercial Loan [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	2,176	2,230
Commercial Portfolio Segment [Member] | Commercial And Industrial Automobile [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	29,020	30,871
Commercial Portfolio Segment [Member] | Commercial And Industrial Automobile [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	27,423	29,150
Commercial Portfolio Segment [Member] | Commercial And Industrial Automobile [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	1,597	1,721
Commercial Portfolio Segment [Member] | Commercial And Industrial Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	2,289	1,882
Commercial Portfolio Segment [Member] | Commercial And Industrial Other [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	1,856	1,509
Commercial Portfolio Segment [Member] | Commercial And Industrial Other [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	433	373
Commercial Portfolio Segment [Member] | Commercial Real Estate Automobile [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	3,302	3,151
Commercial Portfolio Segment [Member] | Commercial Real Estate Automobile [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	3,156	3,015
Commercial Portfolio Segment [Member] | Commercial Real Estate Automobile [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Finance receivables and loans, net	$ 146	$ 136