Revenue by Category (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 4,187	$ 3,339
Revenue Not from Contract with Customer, Other	[1]	1,087	868
Revenues Adjustments For Certain Risk Management Activities Costs	[2]	(2,226)	(1,436)
Total revenues		3,048	2,771
Regulated Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		900	859
NonRegulated Service Monetary Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		1,039	981
NonRegulated Service Commodity Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		49	30
Total revenues		49	30
Other Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		43	38
Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		2,031	1,908
Total revenues		2,003	1,905
Product [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		2,156	1,431
Total revenues		1,058	845
Operating Segments [Member] | Transmission And Gulf Of America [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		1,267	1,108
Revenue Not from Contract with Customer, Other	[1]	5	11
Revenues Adjustments For Certain Risk Management Activities Costs	[2]	0	0
Total revenues		1,272	1,119
Operating Segments [Member] | Transmission And Gulf Of America [Member] | Regulated Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		920	880
Operating Segments [Member] | Transmission And Gulf Of America [Member] | NonRegulated Service Monetary Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		192	145
Operating Segments [Member] | Transmission And Gulf Of America [Member] | NonRegulated Service Commodity Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		23	9
Total revenues		23	9
Operating Segments [Member] | Transmission And Gulf Of America [Member] | Other Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		17	13
Operating Segments [Member] | Transmission And Gulf Of America [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		1,152	1,047
Total revenues		1,135	1,049
Operating Segments [Member] | Transmission And Gulf Of America [Member] | Product [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		115	61
Total revenues		115	61
Operating Segments [Member] | Northeast G And P [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		544	498
Revenue Not from Contract with Customer, Other	[1]	11	11
Revenues Adjustments For Certain Risk Management Activities Costs	[2]	0	0
Total revenues		555	509
Operating Segments [Member] | Northeast G And P [Member] | Regulated Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Operating Segments [Member] | Northeast G And P [Member] | NonRegulated Service Monetary Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		462	444
Operating Segments [Member] | Northeast G And P [Member] | NonRegulated Service Commodity Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		1	5
Total revenues		1	5
Operating Segments [Member] | Northeast G And P [Member] | Other Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		24	24
Operating Segments [Member] | Northeast G And P [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		487	473
Total revenues		497	479
Operating Segments [Member] | Northeast G And P [Member] | Product [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		57	25
Total revenues		57	25
Operating Segments [Member] | West [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		726	700
Revenue Not from Contract with Customer, Other	[1]	(1)	1
Revenues Adjustments For Certain Risk Management Activities Costs	[2]	0	0
Total revenues		725	701
Operating Segments [Member] | West [Member] | Regulated Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Operating Segments [Member] | West [Member] | NonRegulated Service Monetary Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		430	430
Operating Segments [Member] | West [Member] | NonRegulated Service Commodity Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		25	16
Total revenues		25	16
Operating Segments [Member] | West [Member] | Other Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		7	6
Operating Segments [Member] | West [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		462	452
Total revenues		438	437
Operating Segments [Member] | West [Member] | Product [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		264	248
Total revenues		264	248
Operating Segments [Member] | Gas & NGL Marketing Services
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		2,056	1,306
Revenue Not from Contract with Customer, Other	[1]	1,100	833
Revenues Adjustments For Certain Risk Management Activities Costs	[2]	(2,445)	(1,569)
Total revenues	[3]	711	570
Operating Segments [Member] | Gas & NGL Marketing Services | Regulated Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Operating Segments [Member] | Gas & NGL Marketing Services | NonRegulated Service Monetary Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Operating Segments [Member] | Gas & NGL Marketing Services | NonRegulated Service Commodity Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Total revenues	[3]	0	0
Operating Segments [Member] | Gas & NGL Marketing Services | Other Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Operating Segments [Member] | Gas & NGL Marketing Services | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Total revenues	[3]	0	0
Operating Segments [Member] | Gas & NGL Marketing Services | Product [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		2,056	1,306
Total revenues	[3]	739	587
Corporate, Non-Segment | Other Operating Segment
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		155	108
Revenue Not from Contract with Customer, Other	[1]	(27)	12
Revenues Adjustments For Certain Risk Management Activities Costs	[2]	0	0
Total revenues		128	120
Corporate, Non-Segment | Other Operating Segment | Regulated Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Corporate, Non-Segment | Other Operating Segment | NonRegulated Service Monetary Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Corporate, Non-Segment | Other Operating Segment | NonRegulated Service Commodity Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Corporate, Non-Segment | Other Operating Segment | Other Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Corporate, Non-Segment | Other Operating Segment | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Corporate, Non-Segment | Other Operating Segment | Product [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		155	108
Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		(561)	(381)
Revenue Not from Contract with Customer, Other	[1]	(1)	0
Revenues Adjustments For Certain Risk Management Activities Costs	[2]	219	133
Total revenues		(343)	(248)
Intersegment Eliminations [Member] | Regulated Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		(20)	(21)
Intersegment Eliminations [Member] | NonRegulated Service Monetary Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		(45)	(38)
Intersegment Eliminations [Member] | NonRegulated Service Commodity Consideration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		0	0
Intersegment Eliminations [Member] | Other Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		(5)	(5)
Intersegment Eliminations [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		(70)	(64)
Intersegment Eliminations [Member] | Product [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		$ (491)	$ (317)

[1] Revenues not derived from contracts with customers primarily consist of physical product sales related to commodity derivative contracts, realized and unrealized gains and losses associated with Williams’ commodity derivative contracts, which are reported in Net gain (loss) from commodity derivatives in the Consolidated Statement of Income, management fees received for certain services provided to operated equity-method investments, and leasing revenues associated with the Williams headquarters building.

[2] Other adjustments reflect certain costs of Gas & NGL Marketing Services’ risk management activities. As Williams is acting as agent for natural gas marketing customers or engages in energy trading activities, the resulting revenues are presented net of the related costs of those activities in the Consolidated Statement of Income.

[3] As Williams is acting as agent for natural gas marketing customers or engages in energy trading activities, the resulting revenues are presented net of the related costs of those activities.