Revenue Recognition Contract Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Contract With Customer, Liability [Line Items]
Contract with Customer, Liability - Beginning of Period	$ 1,046	$ 1,081
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	34	42
Other Significant Noncash Transaction, Value of Consideration Received	2	2
Contract with Customer, Liability, Revenue Recognized	(66)	(72)
Contract with Customer, Liability - End of Period	1,016	1,053
Transcontinental Gas Pipe Line Company, LLC [Member]
Contract With Customer, Liability [Line Items]
Contract with Customer, Liability - Beginning of Period	173	184
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	0	0
Other Significant Noncash Transaction, Value of Consideration Received	0	0
Contract with Customer, Liability, Revenue Recognized	(2)	(3)
Contract with Customer, Liability - End of Period	171	181
Northwest Pipeline LLC [Member]
Contract With Customer, Liability [Line Items]
Contract with Customer, Liability - Beginning of Period	0	2
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	0	0
Other Significant Noncash Transaction, Value of Consideration Received	0	0
Contract with Customer, Liability, Revenue Recognized	0	(1)
Contract with Customer, Liability - End of Period	$ 0	$ 1