Financing Receivables (Schedule Of Lease Receivables, Net Of Nonrecourse Debt, Associated With Leveraged Lease Portfolio Based On Counterparty Credit Rating) (Detail) (Energy Holdings [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Guarantor Obligations [Line Items]
Lease Receivables, Net of Non-Recourse Debt	$ 705	$ 721
Counterparties' Credit Rating (S&P), AA [Member]
Guarantor Obligations [Line Items]
Lease Receivables, Net of Non-Recourse Debt	20	21
Counterparties' Credit Rating (S&P), A+ [Member]
Guarantor Obligations [Line Items]
Lease Receivables, Net of Non-Recourse Debt	58	73
Counterparties' Credit Rating (S&P), BBB+ - BBB- [Member]
Guarantor Obligations [Line Items]
Lease Receivables, Net of Non-Recourse Debt	316	316
Counterparties' Credit Rating (S&P), B- [Member]
Guarantor Obligations [Line Items]
Lease Receivables, Net of Non-Recourse Debt	166	166
Counterparties' Credit Rating (S&P), CCC+ [Member]
Guarantor Obligations [Line Items]
Lease Receivables, Net of Non-Recourse Debt	134	134
Counterparties' Credit Rating (S&P) Not Rated [Member]
Guarantor Obligations [Line Items]
Lease Receivables, Net of Non-Recourse Debt	$ 11	$ 11