Other Commitments And Other Operating Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commitments And Contingencies [Abstract]
2016	$ 40
2017	41
2018	40
2019	38
2020	37
Thereafter	194
Total	390
Payments for other commitments and operating leases	$ 41	$ 42	$ 40
Property Subject To Or Available For Operating Lease Expiration Beginning Date	2016
Property Subject To Or Available For Operating Lease Expiration Ending Date	2052