Finance Assets, Net (Schedule Of Credit Quality Of Investments In Finance Assets) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Total	$ 2,464	$ 2,680
"AAA/Aaa" To "A-/A3" [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Total	784	961
"BBB+/Baa1" To "BBB-/Baa3" [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Total	925	938
"BB+/Ba1" And Lower [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Total	$ 755	$ 781