Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Pension cost	$ 700	$ 800	$ 1,900
Regulatory liabilities	271,706	388,433
Regulatory Liabilities	416,949	388,591
Defined contribution plan matching contributions expense	2,800	2,700	2,300
Salary and Wage, Excluding Cost of Good and Service Sold [Abstract]
Stock-based compensation expense	1,300	1,200	1,300
Retiree health care and life insurance benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Regulatory liabilities	1,200	1,600	$ 1,700
Other Postretirement Benefit Costs
Defined Benefit Plan Disclosure [Line Items]
Regulatory liabilities	42,200	$ 41,000
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension cost charges to us by Williams	$ 700