Segment Information - Additional Segment Information - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Operating revenues	$ 433,470	$ 462,423
Cost of gas	175,717	205,749
Environmental remediation	5,746	5,375
Operating Segments [Member] | Natural Gas Distribution [Member]
Segment Reporting Information [Line Items]
Natural Gas Distribution revenues	412,987	443,061
Other regulated services	4,877	4,709
Operating revenues	417,864	447,770
Cost of gas	175,773	205,805
Environmental remediation	5,746	5,375
Revenue taxes	18,195	18,975
NGD margin	$ 218,150	$ 217,615