Finance Receivables And Loans, Net (Schedule of Accounts, Notes, Loans and Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	$ 95,281	$ 121,259	$ 95,281	$ 121,259	$ 99,055
Interest and Fee Income, Loans and Leases	(1,119)	(1,141)	(3,393)	(3,374)
Consumer Loans Auto Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	56,450		56,450		53,715
Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	8,772		8,772		9,821
First Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	6,343		6,343		7,173
Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	2,429		2,429		2,648
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	30,059		30,059		35,519
Commercial And Industrial Automobile [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	25,691		25,691		30,270
Commercial And Industrial Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	0		0		0
Commercial And Industrial Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	1,607		1,607		2,697
Commercial Real Estate Automobile [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	2,761		2,761		2,552
Commercial Real Estate Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	0		0		0
Foreign [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	0		0
Foreign [Member] | Consumer Loans Auto Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net					2
Foreign [Member] | Commercial And Industrial Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net					18
loans held-for-investment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	695		695		895
Designated as Hedging Instrument [Member] | Gain (Loss) Recognized in Earnings on Hedged Item [Member] | Interest Rate Contract [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest and Fee Income, Loans and Leases	$ 3	$ 0	$ 3	$ 0