Acquisitions and Divestitures (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Dekatherm	Sep. 30, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	$ 107,335	$ 101,419	$ 409,604	$ 351,160
Operating Income (Loss)	20,113	17,406	94,288	77,518
Unregulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating Income (Loss)	(2,883)	(3,092)	15,777	11,050
Regulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating Income (Loss)	23,538	$ 20,482	79,210	$ 66,376
Elkton Gas [Member] | Regulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	15,900		15,900
Revenues	900		4,700
Operating Income (Loss)	(100)		$ 700
Number of customers acquired through acquisition			7,000
Business Combination, Consideration Transferred			$ 15,600
Business Combination, Working Capital	600		600
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	600		600
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	2,600		2,600
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	4,300		4,300
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Regulatory Liabilities			2,600
Western Natural Gas [Member] | Unregulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	3,500		3,500
Revenues	500		1,900
Operating Income (Loss)	100		400
Business Combination, Consideration Transferred			6,700
Business Combination, Working Capital	300		300
Business Combination, Contingent Consideration, Liability	300		300
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	1,800		1,800
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets	$ 1,400		$ 1,400
Escambia Meter | Regulated Energy [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional Firm Natural Gas Transportation Deliverability | Dekatherm			530,000