Pension Plan And Other Postretirement Benefits (Pension And Other Postretirement Benefit Costs) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	$ 12	$ 4	$ 16	$ 8
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	4	6	8
Interest cost	1	2	3	3
Expected return on plan assets	(1)	(2)	(3)	(4)
Amortization of prior service cost
Amortization of net loss	1		1	$ 1
Curtailment loss	1		1
Settlement loss	$ 8		$ 8