Pension Plan And Other Postretirement Benefits (Pension And Other Postretirement Benefit Costs) (Details) - Pension Benefits [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 4	$ 4
Interest cost	2	1
Expected return on plan assets	$ (2)	$ (2)
Amortization of prior service cost
Amortization of net loss		$ 1
Net periodic benefit cost	$ 4	$ 4