Leases Operating Leases, Future Minimum Payments Receivable (Details) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
		Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Operating Leases, Future Minimum Payments Receivable [Abstract]
Lessor, Operating Lease, Payments to be Received, Remainder of Fiscal Year		$ 204	$ 204
Operating Lease, Lease Income	[1]	70	139
Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals				$ 342
Lessor, Operating Lease, Payments to be Received, Two Years		287	287
Lessor, Operating Lease, Payments to be Received, Three Years		261	261
Lessor, Operating Lease, Payments to be Received, Four Years		227	227
Lessor, Operating Lease, Payments to be Received, Five Years		144	144
Lessor, Operating Lease, Payments to be Received, Thereafter		284	284
Lessor, Operating Lease, Payments to be Received		$ 1,407	$ 1,407

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