Long-Term Investments (Schedule Of Net Investment In Leveraged Leases) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Long-term Investments [Abstract]
Lease Receivables (net of Non-Recourse Debt)	$ 629	$ 631
Estimated Residual Value of Leased Assets	346	519
Total Investment in Rental Receivables	975	1,150
Unearned and Deferred Income	(326)	(366)
Gross Investment in Leases	649	784
Deferred Tax Liabilities	(674)	(724)
Net Investments in Leases	$ (25)	$ 60