Litigation and Environmental - Federal Energy Regulatory Commission Proceedings (Details) - Pending Litigation $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($) claims	Jun. 01, 2018 projects
Hiland Partners Holdings, LLC [Member]
SFPP [Abstract]
Loss Contingency, Damages Sought, Value	$ 225
EPNG [Abstract]
Infrastructures to Build for Settlement | projects		10
Federal Energy Regulatory Commission [Member] | Unfavorable Regulatory Action | EPNG
EPNG [Abstract]
Loss Contingency, Pending Claims, Number | claims	2
Federal Energy Regulatory Commission [Member] | Annual Rate Reductions | Unfavorable Regulatory Action | SFPP
SFPP [Abstract]
Loss Contingency, Damages Sought, Value	$ 50
Federal Energy Regulatory Commission [Member] | Revenue Subject to Refund | Unfavorable Regulatory Action | SFPP
SFPP [Abstract]
Loss Contingency, Damages Sought, Value	$ 425