Revenue Recognition Contract Liabilities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)
Contract with Customer, Liability [Line Items]
Contract with Customer, Liability - Beginning of Period	$ 1,596
Contract With Customer Liability Payments Received and Deferred	314
ContractLiabilityNoncashInterestExpenseSignificantFinancingObligation	16
Variable Interest Entity Nonconsolidated Contract Liability 1	(26)
Contract with Customer, Liability, Revenue Recognized	(451)
Contract with Customer, Liability - End of Period	1,397
Jackalope Gas Gathering Services LLC [Member]
Contract with Customer, Liability [Line Items]
Variable Interest Entity Nonconsolidated Contract Liability 1	$ (52)