Acquisitions (Schedule Of Acquisition and Integration Costs) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Business Acquisition [Line Items]
Acquisition costs		$ 2	$ 23	$ 38
Integration costs	$ 122	56	364	112
Total acquisition and integration costs	122	58	387	150
Verizon Transaction [Member]
Business Acquisition [Line Items]
Acquisition costs		2	23	37
Integration costs	$ 122	44	$ 364	75
Connecticut Operations [Member]
Business Acquisition [Line Items]
Acquisition costs				1
Integration costs		$ 12		$ 37