NATURE OF THE BUSINESS (Details)	6 Months Ended
Mar. 31, 2024 subsidiary customer
Steckman Ridge
Nature of Business [Line Items]
Ownership percentage	50.00%
NJNG
Nature of Business [Line Items]
Total retail customers \| customer	581,600
NJR Retail Holdings Corporation
Nature of Business [Line Items]
Number of principal subsidiaries \| subsidiary	1

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant