Statement of Net Income (Unaudited) - Transco - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Revenues [Abstract]
Revenues	$ 3,048	$ 2,771
Costs and Expenses [Abstract]
Depreciation, depletion, and amortization	585	548
Other Operating Income (Expense), Net	(10)	(17)
Total costs and expenses	1,954	1,759
Operating income (loss)	1,094	1,012
Interest expense	(349)	(349)
Other Nonoperating Income (Expense)	14	31
Net income	691	632
Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	770	732
Costs and Expenses [Abstract]
Cost of natural gas sales	18	24
Utilities Operating Expense, Maintenance and Operations	124	120
General and Administrative Expense	57	51
Depreciation, depletion, and amortization	149	134
Taxes, Miscellaneous	30	28
Other Operating Income (Expense), Net	6	(15)
Total costs and expenses	384	342
Operating income (loss)	386	390
Interest expense	(81)	(81)
Interest Income, Other	8	18
Public Utilities, Allowance for Funds Used During Construction, Additions	9	23
Other Nonoperating Income (Expense)	(1)	(2)
Net income	321	348
Natural Gas, US Regulated | Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	690	652
Natural Gas, Storage | Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	55	48
Natural Gas, Gathering, Transportation, Marketing and Processing | Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	18	24
Product and Service, Other | Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	$ 7	$ 8