Transactions with Major Customers and Affiliates (Details) $ in Thousands		1 Months Ended	12 Months Ended
	Dec. 31, 2019 USD ($)	Jan. 31, 2022 USD ($)	Dec. 31, 2021 USD ($) employee	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Advances to affiliate			$ 1,669,368	$ 642,734
Related party transaction, rate			0.01%
Entity number of employees | employee			0
Expenses, related party			$ 329,700	278,800	$ 304,500
Cash distributions to parent			343,731	1,020,000	824,000
Cash contributions from parent			417,000	115,000	0
Non-cash distribution of investments in subsidiaries	$ 36,600
Subsequent Event [Member]
Related Party Transaction [Line Items]
Cash contributions from parent		$ 128,000
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Operating revenues, related party			37,400	11,400	10,500
Cost of natural gas sales, related party			7,900	5,600	4,000
Expenses, related party			(7,300)	(5,100)	(4,400)
Williams Companies Inc [Member]
Related Party Transaction [Line Items]
Advances from affiliate			1,669,400	642,700
Cash distributions to parent			343,700	1,020,000	824,000
Williams Companies Inc [Member] | Subsequent Event [Member]
Related Party Transaction [Line Items]
Cash distributions to parent		$ 57,500
Atlantic Sunrise Project [Member]
Related Party Transaction [Line Items]
Additions to other financing obligations					25,000
Dominion Energy, Inc.
Revenue, Major Customer [Line Items]
Operating revenues			$ 297,700	$ 248,500	$ 250,700
Percentage of revenue			11.00%	10.00%	10.00%