Commitments And Contingencies (Schedule Of Reconciliation Of Beginning And Ending Accrued Litigated Claims And Non-Litigated Claims) (Details) - Litigated Claims And Non-Litigated Claims [Member] - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Commitments and Contingencies [Line Items]
Balance at the beginning of the period	$ 80	$ 28
Provision for termite damage claims	41	28
Cash payments	(42)	(31)
Balance at the end of the period	$ 79	$ 25