Statement of Net Income (Unaudited) - Transco - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Revenues [Abstract]
Revenues	$ 2,781	$ 2,336	$ 5,829	$ 5,107
Costs and Expenses [Abstract]
Depreciation, depletion, and amortization	605	540	1,190	1,088
Other Operating Income (Expense), Net	13	(27)	3	(44)
Total costs and expenses	1,836	1,640	3,790	3,399
Operating income (loss)	945	696	2,039	1,708
Interest expense	(350)	(339)	(699)	(688)
Other Nonoperating Income (Expense)	16	33	30	64
Net income (loss) attributable to The Williams Companies, Inc.	546	401	1,237	1,033
Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	791	710	1,561	1,442
Costs and Expenses [Abstract]
Cost of natural gas sales	26	22	44	46
Utilities Operating Expense, Maintenance and Operations	117	118	241	238
General and Administrative Expense	53	52	110	103
Depreciation, depletion, and amortization	166	131	315	265
Taxes, Miscellaneous	31	29	61	57
Other Operating Income (Expense), Net	15	(10)	21	(25)
Total costs and expenses	408	342	792	684
Operating income (loss)	383	368	769	758
Interest expense	(81)	(80)	(162)	(161)
Interest Income, Other	7	15	15	33
Public Utilities, Allowance for Funds Used During Construction, Additions	6	27	15	50
Other Nonoperating Income (Expense)	(1)	(1)	(2)	(3)
Net income (loss) attributable to The Williams Companies, Inc.	314	329	635	677
Natural Gas, US Regulated | Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	694	634	1,384	1,286
Natural Gas, Storage | Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	63	48	118	96
Natural Gas, Gathering, Transportation, Marketing and Processing | Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	26	22	44	46
Product and Service, Other | Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	$ 8	$ 6	$ 15	$ 14