Entity tax identification number Entity Tax Identification Number Participant rollover EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Rollover Maximum Maximum [Member] Legal Entity [Axis] Legal Entity [Axis] Adminstrative budget account, increase due to interest EBP, Administration Budget, Increase Due to Interest EBP, Administration Budget, Increase Due to Interest Statistical Measurement [Domain] Statistical Measurement [Domain] EBP, Description of Plan [Table] EBP, Description of Plan [Table] Mutual funds Mutual Fund [Member] Employer matching contribution, second match EBP, Employer Matching Contribution, Second Match [Member] EBP, Employer Matching Contribution, Second Match EBP, Related Party and Party-in-Interest Transactions [Table] EBP, Related Party and Party-in-Interest Transactions [Table] Participant contribution, maximum percentage of eligible base compensation EBP, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage Total deductions EBP, Change in Net Asset Available for Benefit, Decrease Notes receivable from participants, maximum borrowing amount EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount FAIR VALUE MEASUREMENTS EBP, Investment, Fair Value and NAV [Text Block] Notes receivable from participants, minimum borrowing amount EBP, Note Receivable from Participant, Account, Minimum Borrowing, Amount EBP, Nonparticipant-Directed Investment [Abstract] Investments, at fair value EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value Notes receivable from participants, primary residence maximum borrowing term EBP, Note Receivable From Participant, Account, Primary Residence, Maximum Borrowing Term EBP, Note Receivable From Participant, Account, Primary Residence, Maximum Borrowing Term Quoted Market Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Reconciliation of net assets available for benefits EBP, Reconciliation of Financial Statement to Form 5500 [Table Text Block] EBP, Investment, Fair Value and NAV [Abstract] Employer contribution ESOP EBP, Employer Contribution, ESOP [Member] EBP, Employer Contribution, ESOP Administrative budget, decrease due to expenses EBP, Administration Budget, Decrease Due to Expenses EBP, Administration Budget, Decrease Due to Expenses Total assets EBP, Asset Assets: EBP, Asset [Abstract] Statistical Measurement [Axis] Statistical Measurement [Axis] Additions to net assets attributed to: EBP, Change in Net Asset Available for Benefit, Increase [Abstract] EBP, Statement of Change in Net Asset Available for Benefit [Table] EBP, Statement of Change in Net Asset Available for Benefit [Table] Transfers to participant-directed investments EBP, Change in Net Asset Available for Benefit, Transfer to (from) Plan Schedule of investment income EBP, Investment Income [Table Text Block] EBP, Investment Income Payment of Benefits EBP, Payment to Participant [Policy Text Block] Less: Current year contributions receivable from employer per the financial statements EBP, Reconciliation to Form 5500, Contributions, Employers, Decrease From Current Year Conributions Receivable EBP, Reconciliation to Form 5500, Contributions, Employers, Decrease From Current Year Conributions Receivable Amendment Flag Amendment Flag EBP 005 EBP 005 [Member] EBP 005 Basis of Accounting EBP, Basis of Accounting [Policy Text Block] INVESTMENTS EBP, Nonparticipant-Directed Investment [Text Block] Less: Current year contributions receivable from participants per the financial statements EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Current Year Contributions Not Yet Paid EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Current Year Contributions Not Yet Paid EBP, Schedule of Asset Held for Investment [Table] EBP, Schedule of Asset Held for Investment [Table] Investment, number of shares (in shares) EBP, Investment, Number of Shares EBP, Nonparticipant-Directed Investment [Line Items] EBP, Nonparticipant-Directed Investment [Line Items] EBP, Description of Plan and Accounting Change [Abstract] Receivables: EBP, Receivable [Abstract] Schedule of instruments measured at fair value EBP, Investment, Fair Value and NAV [Table Text Block] Investments [Domain] Investments [Domain] Use of Estimates EBP, Use of Estimate [Policy Text Block] FORM 5500, SCHEDULE H, PART IV, LINE 4i---SCHEDULE OF ASSETS (HELD AT END OF YEAR) EBP, Schedule of Asset Held for Investment [Text Block] Cover [Abstract] Notes receivable from participants, general loan maximum borrowing term EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term EBP, Form 5500, Contributions From Participant [Abstract] EBP, Form 5500, Contributions From Participant [Abstract] EBP, Form 5500, Contributions From Participant RISKS AND UNCERTAINTIES EBP, Risk and Uncertainty [Text Block] Less: Changes in amounts due from participants** EBP, Reconciliation to Form 5500, Change in Net Asset Available for Benefit, Prior Period, Decrease In Amounts Due From Employer, Decrease in Amounts Due From Participants EBP, Reconciliation to Form 5500, Change in Net Asset Available for Benefit, Prior Period, Decrease In Amounts Due From Employer, Decrease in Amounts Due From Participants Add: Prior year contributions receivable from participants per the financial statements EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Prior Year Contributions Not Yet Paid EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Prior Year Contributions Not Yet Paid Employer Employer contribution EBP, Change in Net Asset Available for Benefit, Increase from Employer Contribution, Cash Minimum Minimum [Member] Investment Type [Axis] Investment Type [Axis] Interest income from notes receivable from participants EBP, Change in Net Asset Available for Benefit, Increase from Interest Income on Note Receivable from Participant Employer Matching Contribution [Domain] EBP, Employer Matching Contribution [Domain] Employer Matching Contribution [Domain] Total contributions EBP, Change in Net Asset Available for Benefit, Increase from Contribution Participants Contributions received from participants per the financial statements EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Excluding Rollover Net appreciation in fair value of investments Net appreciation in fair value of investments EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Gain (Loss) on Investment EBP, Description of Plan [Line Items] EBP, Description of Plan [Line Items] Plan number EBP, Plan Number EBP, Form 5500 Caption, Net Income (Loss) [Abstract] EBP, Form 5500 Caption, Net Income (Loss) [Abstract] EBP, Investment, Fair Value and NAV [Line Items] EBP, Investment, Fair Value and NAV [Line Items] PLAN DESCRIPTION EBP, Description of Plan [Text Block] Requisite service period EBP, Requisite Service Period EBP, Requisite Service Period EBP, Statement of Change in Net Asset Available for Benefit [Line Items] EBP, Statement of Change in Net Asset Available for Benefit [Line Items] EBP, Statement of Net Asset Available for Benefit [Table] EBP, Statement of Net Asset Available for Benefit [Table] EBP, Schedule of Asset Held for Investment [Line Items] EBP, Schedule of Asset Held for Investment [Line Items] NJR stock EBP, Employer, Common Stock [Member] EBP, Schedule of Asset Held for Investment [Abstract] EBP, Form 5500 Caption, Net Assets [Abstract] EBP, Form 5500 Caption, Net Assets [Abstract] EBP, Nonparticipant-Directed Investment [Table] EBP, Nonparticipant-Directed Investment [Table] EBP, Accounting Policy [Table] EBP, Accounting Policy [Table] Schedule of non-participant directed investments EBP, Nonparticipant-Directed Investment [Table Text Block] Total additions EBP, Change in Net Asset Available for Benefit, Increase Investment income: EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment [Abstract] Investment, Identifier [Axis] Investment, Identifier [Axis] Administrative fees Administrative fees EBP, Change in Net Asset Available for Benefit, Decrease from Administrative Expense Total Asset Held for Investment EBP, Asset Held for Investment Employer contributin, special contribution percentage EBP, Employer Contribution, Special Contribution Percentage EBP, Employer Contribution, Special Contribution Percentage Document Information [Line Items] Document Information [Line Items] EBP, Change in Net Asset Available for Benefit, Increase (Decrease) [Abstract] EBP, Change in Net Asset Available for Benefit, Increase (Decrease) [Abstract] Adminstrative budget account EBP, Administration Budget EBP, Administration Budget EBP, Risk and Uncertainty [Line Items] EBP, Risk and Uncertainty [Line Items] EBP, Risk and Uncertainty [Table] EBP, Risk and Uncertainty [Table] Employer contribution, participant compensation percentage matched EBP, Employer Contribution, Participant Compensation Matched, Percentage EBP, Statement of Change in Net Asset Available for Benefit [Abstract] Other Significant Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Net change EBP, Change in Net Asset Available for Benefit, Increase (Decrease), Including Transfers EBP, Change in Net Asset Available for Benefit, Increase (Decrease), Including Transfers Retirement Year Funds Common Collective Trust, Retirement Year Funds [Member] Common Collective Trust, Retirement Year Funds Employer special per capita contribution EBP Employer Special Per Capita Contribution [Member] EBP Employer Special Per Capita Contribution Employer special contribution, represented employees EBP, Employer Contribution Represented Employees [Member] EBP, Employer Contribution Represented Employees Net income per Form 5500 EBP, Form 5500 Caption, Net Income (Loss) EBP, Tax Status [Table] EBP, Tax Status [Table] Net increase Increase in net assets per the financial statements EBP, Change in Net Asset Available for Benefit, Increase (Decrease) EXEMPT PARTY-IN-INTEREST TRANSACTIONS EBP, Related Party and Party-in-Interest Transactions [Text Block] Employer matching contribution, first match EBP, Employer Matching Contribution, First Match [Member] EBP, Employer Matching Contribution, First Match EBP, Related Party and Party-in-Interest Transactions [Abstract] EBP, Form 5500, Contributions From Employer [Abstract] EBP, Form 5500, Contributions From Employer [Abstract] EBP, Form 5500, Contributions From Employer EBP, Accounting Policy, Accounting Standard Update, and Change in Accounting Principle [Abstract] Total receivables EBP, Receivable Employer contributions EBP, Employer Contribution, Receivable Participate contribution, automatic deferral rate EBP, Participant Contribution, Automatic, Deferral Rate Benefits paid to participants Benefits paid to participants EBP, Change in Net Asset Available for Benefit, Decrease from Payment to Participant Dividends EBP, Change in Net Asset Available for Benefit, Increase from Dividend Income on Investment Investment, fees paid EBP, Investment, Fees Paid EBP, Investment, Fees Paid Current Value EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Current Value Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] EBP, Statement of Net Asset Available for Benefit [Abstract] EBP, Accounting Policy [Line Items] EBP, Accounting Policy [Line Items] EBP, Tax Status [Abstract] Less: Changes in amounts due from employer* EBP, Reconciliation to Form 5500, Change in Net Asset Available for Benefit, Prior Period, Decrease In Amounts Due From Employer EBP, Reconciliation to Form 5500, Change in Net Asset Available for Benefit, Prior Period, Decrease In Amounts Due From Employer Employer special contribution, 1-5 years of service EBP, Employer Special Contribution, One Year to Five Years of Service [Member] EBP, Employer Special Contribution, One Year to Five Years of Service EBP, Reconciliation of Financial Statement to Form 5500 [Table] EBP, Reconciliation of Financial Statement to Form 5500 [Table] Stable Value Fund Common Collective Trust, Stable Value Fund [Member] Common Collective Trust, Stable Value Fund EBP, Reconciliation of Financial Statement to Form 5500 [Line Items] EBP, Reconciliation of Financial Statement to Form 5500 [Line Items] Administrative Expenses EBP, Expense [Policy Text Block] EBP, Employer Contribution, Type of Contribution [Domain] EBP, Employer Contribution, Type of Contribution [Domain] EBP, Employer Contribution, Type of Contribution [Domain] RECONCILIATION OF FINANCIAL STATEMENTS TO FORM 5500 EBP, Reconciliation of Financial Statement to Form 5500 [Text Block] Notes receivable from participants, basis spread on variable interest rate EBP, Participant Loan, Basis Spread On Variable Rate EBP, Participant Loan, Basis Spread On Variable Rate Valuation of Investments and Income Recognition EBP, Investment [Policy Text Block] Participant contributions EBP, Participant Contribution, Receivable Total Level 1, Level 2, and Level 3 Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] Document Type Document Type PLAN TERMINATION EBP, Plan Termination [Text Block] Entity Central Index Key Entity Central Index Key Less: Amounts due from employer per the financial statements EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Employer Contributions Not Yet Paid EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Employer Contributions Not Yet Paid Notes receivable from participants, interest rate EBP, Asset Held for Investment, Participant Loan, Interest Rate EBP, Reconciliation of Financial Statement to Form 5500 [Abstract] Common Collective Trust Common Collective Trust [Member] Contributions received from participants per Form 5500 EBP, Form 5500 Caption, Contributions, Participants Net assets available for benefits: EBP, Net Asset Available for Benefit [Abstract] EBP, Risk and Uncertainty [Abstract] EBP, Tax Status [Line Items] EBP, Tax Status [Line Items] EBP, Employer Contribution, Type of Contribution [Axis] EBP, Employer Contribution, Type of Contribution [Axis] EBP, Employer Contribution, Type of Contribution Deductions from net assets attributed to: EBP, Change in Net Asset Available for Benefit, Decrease [Abstract] Notes receivable from participants EBP, Note Receivable from Participant Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES EBP, Summary of Accounting Policy [Text Block] Entity Registrant Name Entity Registrant Name Contributions received from employer per Form 5500 EBP, Form 5500 Caption, Contributions, Employers Cost EBP, Investment, Excluding Plan Interest in Master Trust, Cost FEDERAL INCOME TAX STATUS EBP, Tax Status [Text Block] Notes receivable from participants, maximum borrowing percentage EBP, Note Receivable from Participant, Account, Maximum Borrowing, to Total Account, Percentage EBP, Participant-Directed and Nonparticipant-Directed Status [Domain] EBP, Participant-Directed and Nonparticipant-Directed Status [Domain] Add: Prior year contributions receivable from employer per the financial statements EBP, Reconciliation to Form 5500, Contributions, Employers, Increase From Prior Year Contributions Receivable EBP, Reconciliation to Form 5500, Contributions, Employers, Increase From Prior Year Contributions Receivable EBP, Participant-Directed and Nonparticipant-Directed Status [Axis] EBP, Participant-Directed and Nonparticipant-Directed Status [Axis] Document Information [Table] Document Information [Table] Non-Participant Directed Investments EBP, Nonparticipant-Directed [Member] Employer special contribution, non-prepresented employees EBP, Employer Contribution Non-Represented Employees [Member] EBP, Employer Contribution Non-Represented Employees Miscellaneous receipts (expenses) EBP, Change in Net Asset Available for Benefit, Increase From Miscellaneous Receipts (Expenses) EBP, Change in Net Asset Available for Benefit, Increase From Miscellaneous Receipts (Expenses) Notes Receivable from Participants EBP, Note Receivable from Participant [Policy Text Block] Net investment income EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment Redemption Notice Period EBP, Fair Value, Investment, NAV, Redemption, Notice Period EBP, Related Party and Party-in-Interest Transactions [Line Items] EBP, Related Party and Party-in-Interest Transactions [Line Items] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Net assets available for benefits Beginning of year End of year Net assets available for benefits per the financial statements EBP, Net Asset Available for Benefit Entity [Domain] Entity [Domain] Contributions: EBP, Change in Net Asset Available for Benefit, Increase from Contribution [Abstract] Adminstrative budget account, increase in allocation EBP, Administration Budget, Increase Due to Allocation EBP, Administration Budget, Increase Due to Allocation Employer special contribution, 5+ years of service EBP, Employer Special Contribution, Five Years Or More of Service [Member] EBP, Employer Special Contribution, Five Years Or More of Service Employer matching contribution EBP Employer Matching Contribution [Member] EBP Employer Matching Contribution Forfeited non-vested accounts balance EBP, Forfeited Nonvested Account Employer contribution, matching percentage EBP, Employer Contribution, Matching Percentage Net assets available for benefits per Form 5500 EBP, Form 5500 Caption, Net Assets Less: Amounts due from participants per the financial statements EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Participant Contributions Not Yet Paid EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Participant Contributions Not Yet Paid Employer contribution, vesting percentage EBP, Employer Contribution Vesting Percentage Company contribution and/ or investment earning percentage vesting to the participant in Company Matching Contributions, Fixed Rate Contributions, Discretionary Profit-Sharing Contributions, Qualified Non-Elective Contributions, and Disability Contributions, upon completion of minimum service period or attainment of maximum vesting age Fair Value Measured at Net Asset Value Per Share Fair Value Measured at Net Asset Value Per Share [Member] EBP, Investment, Fair Value and NAV [Table] EBP, Investment, Fair Value and NAV [Table] Employer Matching Contribution [Axis] EBP, Employer Matching Contribution [Axis] EBP, Employer Matching Contribution EBP, Statement of Net Asset Available for Benefit [Line Items] EBP, Statement of Net Asset Available for Benefit [Line Items] Participant contribution, minimum percentage of eligible base compensation EBP, Participant Contribution, Pretax, Minimum Annual Compensation to Total Compensation, Percentage EBP, Participant Contribution, Pretax, Minimum Annual Compensation to Total Compensation, Percentage