Derivative Assets And Liabilities Outstanding Commodity Derivatives (Details)		6 Months Ended
		Jun. 30, 2020 barrels Megawatt MMbtu bbl bushels	Dec. 31, 2019 barrels Megawatt MMbtu bbl bushels
Document Period End Date		Jun. 30, 2020
Fixed Swaps/Futures [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Natural Gas [Member]
Notional Volume		(10,708)	(3,085)
Fixed Swaps/Futures [Member] | Non Trading [Member] | Fair Value Hedging Derivatives [Member] | Short [Member] | Natural Gas [Member]
Notional Volume		(43,235)	(31,780)
Fixed Swaps/Futures [Member] | Trading [Member] | Mark-To-Market Derivatives [Member] | Long [Member] | Natural Gas [Member]
Notional Volume		(373)	(1,483)
Forward Physical Contracts [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Natural Gas [Member]
Notional Volume		(23,980)	(13,364)
Forwards Swaps [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Natural Gas Liquids [Member]
Notional Volume | bbl		(8,830)	(1,300)
Forwards Swaps [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member] | Long [Member] | Crude Oil [Member]
Notional Volume | bbl		(3,393)	(4,465)
Forwards Swaps [Member] | Trading [Member] | Mark-To-Market Derivatives [Member] | Long [Member] | Power [Member]
Notional Volume | Megawatt		(1,338,776)	(3,213,450)
Hedged Item - Inventory (MMBtu) [Member] | Non Trading [Member] | Fair Value Hedging Derivatives [Member] | Long [Member] | Natural Gas [Member]
Notional Volume		(43,235)	(31,780)
Basis Swaps IFERC/NYMEX [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Natural Gas [Member]
Notional Volume		(27,713)	(18,923)
Basis Swaps IFERC/NYMEX [Member] | Non Trading [Member] | Fair Value Hedging Derivatives [Member] | Short [Member] | Natural Gas [Member]
Notional Volume		(43,235)	(31,780)
Basis Swaps IFERC/NYMEX [Member] | Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Natural Gas [Member]
Notional Volume	[1]	(20,433)	(35,208)
Options - Calls [Member] | Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Power [Member]
Notional Volume | Megawatt		(1,268,532)	(2,704,330)
Swing Swaps IFERC [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Natural Gas [Member]
Notional Volume		(35,590)	(9,265)
Future [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member]
Notional Volume | bushels		0
Future [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Refined Products [Member]
Notional Volume | barrels		(3,370)	(2,473)
Future [Member] | Non Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Corn [Member]
Notional Volume | bushels			(1,210)
Future [Member] | Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Power [Member]
Notional Volume | Megawatt			(353,527)
Future [Member] | Trading [Member] | Mark-To-Market Derivatives [Member] | Long [Member] | Power [Member]
Notional Volume | Megawatt		(204,090)
Options - Puts [Member] | Trading [Member] | Mark-To-Market Derivatives [Member] | Short [Member] | Power [Member]
Notional Volume | Megawatt		(340,743)
Put Option [Member] | Trading [Member] | Mark-To-Market Derivatives [Member] | Long [Member] | Power [Member]
Notional Volume | Megawatt			(51,615)

[1] Includes aggregate amounts for open positions related to Houston Ship Channel, Waha Hub, NGPL TexOk, West Louisiana Zone and Henry Hub locations