Leases (Supplemental Cash Flow Information And Other Information For Leases) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating cash flows for operating leases	$ 24
Operating cash flows for finance leases	5
Financing cash flows for finance leases	34
ROU assets obtained in exchange for lease obligations: Operating leases	12
ROU assets obtained in exchange for lease obligations: Finance leases	$ 43
Weighted Average Remaining Lease Term (in years): Operating leases	10 years 6 months 29 days
Weighted Average Remaining Lease Term (in years): Finance leases	3 years 4 months 2 days
Weighted Average Discount Rate: Operating leases	5.55%
Weighted Average Discount Rate: Finance leases	4.13%