Litigation and Environmental - Environmental Matters (Details)				240 Months Ended
	Apr. 16, 2019	Mar. 29, 2019 Parties	Nov. 08, 2013 Parties	Dec. 31, 1969	Jan. 31, 2015 cases
Loss Contingencies [Line Items]
Percentage of Response Costs	35.00%
Rare Metals Inc.
Loss Contingencies [Line Items]
Number of Uranium Mines				20
Parish of Plaquemines, Louisiana | Coastal Zone | TGP
Loss Contingencies [Line Items]
Loss Contingency, Number of Defendants | Parties			17
Parish Orleans, Louisiana | Coastal Zone | SNG
Loss Contingencies [Line Items]
Loss Contingency, Number of Defendants | Parties		10
Judicial District of Louisiana | Coastal Zone
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number					40
Judicial District of Louisiana | Coastal Zone | TGP
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number					1
Judicial District of Louisiana | Coastal Zone | SNG
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number					1
Louisiana Landowner Coastal Erosion Litigation | Judicial District of Louisiana | TGP and SNG
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number					2
Louisiana Landowner Coastal Erosion Litigation | Judicial District of Louisiana | TGP
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number					2
Louisiana Landowner Coastal Erosion Litigation | Judicial District of Louisiana | SNG
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number					2