Leases (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Leases, Rent Expense, Net			$ 53	$ 50
Capital Leased Assets, Gross			715
Less: Accumulated depreciation		$ 6,851	6,832
Operating Lease, Lease Income	[1]	$ 341
Lessee, Finance Lease, Term of Contract		30 years
Assets Held under Capital Leases [Member]
Less: Accumulated depreciation			$ 353

[1] Revenues associated with our operating leases are included in Commodity revenue and other revenue on our Consolidated Statement of Operations.