Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Valuation Allowance for Deferred Tax Assets
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 7,392	$ 0
Charged to Costs and Expenses	14,176	7,392
Regulated Asset	0	0
Charged to Other Accounts	0	0
Deductions	0	0
Balance at End of Period	21,568	7,392	$ 0
Provision for Uncollectibles
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	30,582	19,829	18,842
Charged to Costs and Expenses	10,159	9,558	10,432
Regulated Asset	7,012	10,953	0
Charged to Other Accounts	592	909	(292)
Deductions	6,582	10,667	9,153
Balance at End of Period	41,763	30,582	19,829
South Jersey Gas Company | Provision for Uncollectibles
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	17,359	14,032	13,643
Charged to Costs and Expenses	7,794	6,209	7,193
Regulated Asset	3,119	4,845	0
Charged to Other Accounts	160	424	(292)
Deductions	3,266	8,151	6,512
Balance at End of Period	$ 25,166	$ 17,359	$ 14,032