Statement of Net Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating Revenue
Operating revenues	$ 439,858	$ 447,335	$ 443,558
Operating Expenses:
Operation and maintenance	88,005	84,260	76,016
General and administrative	50,524	51,682	49,204
Depreciation and amortization	111,434	114,384	113,180
Taxes, other than income taxes	12,297	17,039	16,836
Regulatory charges resulting from tax rate changes	0	19,621	23,580
Other (income) expense, net	(16,519)	1,712	1,449
Total operating expenses	245,741	288,698	280,265
Operating Income	194,117	158,637	163,293
Other (Income) and Other Expenses:
Interest expense	27,863	30,987	29,986
Allowance for equity and borrowed funds used during construction (AFUDC)	(3,846)	(2,950)	(1,606)
Miscellaneous other (income) expense, net	(9,619)	(6,174)	(595)
Total other (income) and other expenses	14,398	21,863	27,785
Net Income	179,719	136,774	135,508
Natural gas transportation
Operating Revenue
Operating revenues	414,647	429,526	428,136
Natural gas storage
Operating Revenue
Operating revenues	15,298	13,104	12,883
Other
Operating Revenue
Operating revenues	$ 9,913	$ 4,705	$ 2,539