Segment Disclosures Recon from Segment to Consolidated - Revenues (Details) - USD ($) $ in Millions		6 Months Ended	12 Months Ended
		Dec. 31, 2021	Dec. 31, 2021		Dec. 31, 2020		Dec. 31, 2019
Segment revenues [Line Items]
Revenues			$ 10,627		$ 7,719		$ 8,201
Other financial information:
Additions to long-lived assets			1,855		1,283		2,911
Proportional Modified EBITDA Equity Method Investments			970		749		746
Intersegment Eliminations [Member]
Segment revenues [Line Items]
Revenues			(697)		(256)		(280)
Other financial information:
Additions to long-lived assets			0		0		0
Proportional Modified EBITDA Equity Method Investments			0		0		0
Operating Segments [Member] | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues			3,786		3,469		3,640
Other financial information:
Additions to long-lived assets			861		706		1,341
Proportional Modified EBITDA Equity Method Investments			183		166		177
Operating Segments [Member] | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues			1,634		1,529		1,500
Other financial information:
Additions to long-lived assets			164		137		1,245
Proportional Modified EBITDA Equity Method Investments			682		473		454
Operating Segments [Member] | West [Member]
Segment revenues [Line Items]
Revenues			5,645		2,943		3,311
Other financial information:
Additions to long-lived assets			209		318		304
Proportional Modified EBITDA Equity Method Investments			105		110		115
Operating Segments [Member] | Other [Member]
Segment revenues [Line Items]
Revenues			345		34		30
Other financial information:
Additions to long-lived assets			620		122		21
Proportional Modified EBITDA Equity Method Investments			0		0		0
Operating Segments [Member] | Sequent
Segment revenues [Line Items]
Revenues			(86)	[1]	0		0
Other financial information:
Additions to long-lived assets			1	[1]	0		0
Proportional Modified EBITDA Equity Method Investments			0		0		0
Service [Member]
Segment revenues [Line Items]
Revenues			6,001		5,924		5,933
Service [Member] | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues			3,310		3,207		3,261
Service [Member] | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues			1,490		1,416		1,291
Service [Member] | West [Member]
Segment revenues [Line Items]
Revenues			1,181		1,280		1,364
Service [Member] | Other [Member]
Segment revenues [Line Items]
Revenues			20		21		17
Service [Member] | Sequent
Segment revenues [Line Items]
Revenues			0	[1]	0		0
Service [Member] | Intersegment Eliminations [Member]
Segment revenues [Line Items]
Revenues			(165)		(112)		(110)
Service [Member] | Intersegment Eliminations [Member] | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues			(75)		(50)		(50)
Service [Member] | Intersegment Eliminations [Member] | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues			(38)		(49)		(47)
Service [Member] | Intersegment Eliminations [Member] | West [Member]
Segment revenues [Line Items]
Revenues			(40)		0		0
Service [Member] | Intersegment Eliminations [Member] | Other [Member]
Segment revenues [Line Items]
Revenues			(12)		(13)		(13)
Service [Member] | Intersegment Eliminations [Member] | Sequent
Segment revenues [Line Items]
Revenues			0	[1]	0		0
Service [Member] | Operating Segments [Member] | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues			3,385		3,257		3,311
Service [Member] | Operating Segments [Member] | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues			1,528		1,465		1,338
Service [Member] | Operating Segments [Member] | West [Member]
Segment revenues [Line Items]
Revenues			1,221		1,280		1,364
Service [Member] | Operating Segments [Member] | Other [Member]
Segment revenues [Line Items]
Revenues			32		34		30
Service [Member] | Operating Segments [Member] | Sequent
Segment revenues [Line Items]
Revenues			0	[1]	0		0
NonRegulated Service Commodity Consideration [Member]
Segment revenues [Line Items]
Revenues			238		129		203
NonRegulated Service Commodity Consideration [Member] | Intersegment Eliminations [Member]
Segment revenues [Line Items]
Revenues			0		0		0
NonRegulated Service Commodity Consideration [Member] | Operating Segments [Member] | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues			52		21		41
NonRegulated Service Commodity Consideration [Member] | Operating Segments [Member] | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues			7		7		12
NonRegulated Service Commodity Consideration [Member] | Operating Segments [Member] | West [Member]
Segment revenues [Line Items]
Revenues			179		101		150
NonRegulated Service Commodity Consideration [Member] | Operating Segments [Member] | Other [Member]
Segment revenues [Line Items]
Revenues			0		0		0
NonRegulated Service Commodity Consideration [Member] | Operating Segments [Member] | Sequent
Segment revenues [Line Items]
Revenues			0	[1]	0		0
Product [Member]
Segment revenues [Line Items]
Revenues			4,536		1,671		2,063
Product [Member] | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues			231		144		217
Product [Member] | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues			13		16		115
Product [Member] | West [Member]
Segment revenues [Line Items]
Revenues			4,117		1,511		1,731
Product [Member] | Other [Member]
Segment revenues [Line Items]
Revenues			138		0		0
Product [Member] | Sequent
Segment revenues [Line Items]
Revenues			37	[1]	0		0
Product [Member] | Intersegment Eliminations [Member]
Segment revenues [Line Items]
Revenues			(532)		(144)		(170)
Product [Member] | Intersegment Eliminations [Member] | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues			(118)		(47)		(71)
Product [Member] | Intersegment Eliminations [Member] | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues			(86)		(41)		(35)
Product [Member] | Intersegment Eliminations [Member] | West [Member]
Segment revenues [Line Items]
Revenues			(213)		(56)		(64)
Product [Member] | Intersegment Eliminations [Member] | Other [Member]
Segment revenues [Line Items]
Revenues			(195)		0		0
Product [Member] | Intersegment Eliminations [Member] | Sequent
Segment revenues [Line Items]
Revenues			80	[1]	0		0
Product [Member] | Operating Segments [Member] | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues			349		191		288
Product [Member] | Operating Segments [Member] | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues			99		57		150
Product [Member] | Operating Segments [Member] | West [Member]
Segment revenues [Line Items]
Revenues			4,330		1,567		1,795
Product [Member] | Operating Segments [Member] | Other [Member]
Segment revenues [Line Items]
Revenues			333		0		0
Product [Member] | Operating Segments [Member] | Sequent
Segment revenues [Line Items]
Revenues		$ (43)	(43)	[1]	0		0
Energy Commodities and Service
Segment revenues [Line Items]
Revenues	[2]		(148)		(5)		2
Energy Commodities and Service | Transmission And Gulf Of Mexico [Member]
Segment revenues [Line Items]
Revenues	[2]		0		0		0
Energy Commodities and Service | Northeast G And P [Member]
Segment revenues [Line Items]
Revenues	[2]		0		0		0
Energy Commodities and Service | West [Member]
Segment revenues [Line Items]
Revenues	[2]		(85)		(5)		2
Energy Commodities and Service | Other [Member]
Segment revenues [Line Items]
Revenues	[2]		(20)		0		0
Energy Commodities and Service | Sequent
Segment revenues [Line Items]
Revenues		$ (43)	(43)	[1],[2]	0	[2]	0	[2]
Energy Commodities and Service | Intersegment Eliminations [Member]
Segment revenues [Line Items]
Revenues	[2]		$ 0		$ 0		$ 0

[1] Sequent nets revenues from marketing and trading activities with the associated costs.

[2] We record transactions that qualify as derivatives at fair value with changes in fair value recognized in earnings in the period of change and characterized as unrealized gains or losses. Gains and losses on derivatives held for energy trading purposes are presented on a net basis in revenue.