Other Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Accrued Liabilities [Line Items]
Interest on debt	$ 350	$ 322
Employee costs	285	197
Contract liabilities (Note 5)	170	159
Alaska refinery contamination litigation (Note 1)	0	134
Asset Retirement Obligation, Current	91	106
Regulatory Liability, Current	85	77
Operating lease liabilities (Note 14)	26	24
Other, including accrued loss contingencies	353	265
Other current liabilities	$ 1,360	$ 1,284
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Transcontinental Gas Pipe Line Company, LLC [Member]
Accrued Liabilities [Line Items]
Interest on debt	$ 76	$ 76
Contract liabilities (Note 5)	10	10
Asset Retirement Obligation, Current	22	96
Customer Deposits	38	35
Regulatory Liability, Current	58	49
Operating lease liabilities (Note 14)	6	6
Other, including accrued loss contingencies	57	69
Other current liabilities	$ 181	$ 190
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Northwest Pipeline LLC [Member]
Accrued Liabilities [Line Items]
Interest on debt	$ 6	$ 6
Accrual for Taxes Other than Income Taxes, Current	8	7
Asset Retirement Obligation, Current	0	1
Exchange Gas Due To Others	10	5
Regulatory Liability, Current	20	21
Operating lease liabilities (Note 14)	1	1
Other, including accrued loss contingencies	10	15
Other current liabilities	$ 34	$ 34
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities