Investing Activities (Details) - USD ($) $ in Millions			3 Months Ended	12 Months Ended
		Aug. 01, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Investments [Line Items]
Equity-method investments			$ 4,614	$ 4,107	$ 4,614	$ 5,048
Equity-method investment, difference between carrying amount and underlying equity			773	634	773
Equity-method investment, payments to purchase or contributions				114	141	166
Distributions from equity-method investees (Note 8)				789	796	865
Current assets			4,513	2,661	4,513	3,797
Current liabilities			(5,830)	(5,312)	(5,830)
Revenues				10,503	10,907	10,965
Net income				2,346	3,303	2,117
Proceeds from dispositions of equity-method investments (Note 8)				161	0	0
Equity Method Investment, Realized Gain (Loss) on Disposal				149	0	0
Gain on remeasurement of equity-method investment (Note 2)				127	30	0
Investment Income, Interest				67	79	15
Investment Income Nonoperating Other				0	(1)	1
Other investing income (loss) - net				343	108	16
Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member]
Schedule of Investments [Line Items]
Current assets			669	564	669
Noncurrent assets			11,058	9,439	11,058
Current liabilities			(358)	(1,146)	(358)
Noncurrent liabilities			(3,619)	(2,383)	(3,619)
Revenues				2,880	3,714	5,520
Operating income				1,190	966	1,268
Net income				$ 987	748	1,102
Appalachia Midstream Investments [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage				66.00%
Equity-method investments	[1]		2,886	$ 2,810	2,886
Equity-method investment, difference between carrying amount and underlying equity			1,100	1,000	1,100
Equity-method investment, payments to purchase or contributions				74	59	83
Distributions from equity-method investees (Note 8)				$ 407	405	415
Blue Racer Midstream LLC [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage				50.00%
Equity-method investments			398	$ 366	398
Distributions from equity-method investees (Note 8)				$ 95	62	49
Blue Racer Midstream LLC [Member] | Northeast G And P [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage				50.00%
Overland Pass Pipeline Company LLC [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage				50.00%
Equity-method investments			387	$ 385	387
Equity-method investment, payments to purchase or contributions				2	1	0
Distributions from equity-method investees (Note 8)				$ 90	56	34
Discovery Producer Services LLC [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage				100.00%
Equity-method investments	[2]		361	$ 0	361
Equity-method investment, payments to purchase or contributions				37	40	41
Distributions from equity-method investees (Note 8)				$ 22	49	49
Gulfstream Natural Gas System, LLC [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage				50.00%
Equity-method investments			210	$ 196	210
Equity-method investment, payments to purchase or contributions				0	0	14
Distributions from equity-method investees (Note 8)				$ 103	98	89
Laurel Mountain Midstream, LLC [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage				69.00%
Equity-method investments			184	$ 171	184
Distributions from equity-method investees (Note 8)				$ 29	42	112
Laurel Mountain Midstream, LLC [Member] | Northeast G And P [Member]
Schedule of Investments [Line Items]
Equity Method Investment, Ownership Percentage				69.00%
Rocky Mountain Midstream Holdings LLC [Member]
Schedule of Investments [Line Items]
Distributions from equity-method investees (Note 8)				$ 0	49	52
Other [Member]
Schedule of Investments [Line Items]
Equity-method investments			188	179	188
Equity-method investment, payments to purchase or contributions				0	3	12
Distributions from equity-method investees (Note 8)				43	35	65
Aux Sable Liquid Products LP [Member]
Schedule of Investments [Line Items]
Equity-method investment, payments to purchase or contributions				1	38	0
Cardinal Pipeline Company, LLC
Schedule of Investments [Line Items]
Equity-method investment, payments to purchase or contributions				0	0	16
Aux Sable Liquid Products Inc And Aux Sable Liquid Products LP And Aux Sable Midstream LLC | Northeast G And P [Member]
Schedule of Investments [Line Items]
Proceeds from dispositions of equity-method investments (Note 8)		$ 161
Equity Method Investment, Realized Gain (Loss) on Disposal		149		149	0	0
RMM Acquisition
Schedule of Investments [Line Items]
Gain on remeasurement of equity-method investment (Note 2)			$ 30	0	30	0
Discovery Acquisition
Schedule of Investments [Line Items]
Gain on remeasurement of equity-method investment (Note 2)		$ 127		$ 127	$ 0	$ 0

[1] Includes equity-method investments in multiple gathering systems in the Marcellus Shale region with an approximate average 66 percent interest.

[2] Discovery is a wholly owned subsidiary of Williams as of August 1, 2024. See Note 3 – Acquisitions and Divestitures.