v3.26.1
FAIR VALUE MEASUREMENTS (Details) - EBP 005 - USD ($)
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value $ 392,060,794 $ 356,135,387
NJR stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 45,700,000  
Total Level 1, Level 2, and Level 3    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 210,440,272 329,228,018
Total Level 1, Level 2, and Level 3 | Mutual funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 164,774,799 277,341,351
Total Level 1, Level 2, and Level 3 | NJR stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 45,665,473 51,886,667
Quoted Market Prices in Active Markets for Identical Assets (Level 1)    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 210,440,272 329,228,018
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | Mutual funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 164,774,799 277,341,351
Quoted Market Prices in Active Markets for Identical Assets (Level 1) | NJR stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 45,665,473 51,886,667
Other Significant Observable Inputs (Level 2)    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 0 0
Other Significant Observable Inputs (Level 2) | Mutual funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 0 0
Other Significant Observable Inputs (Level 2) | NJR stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 0 0
Significant Unobservable Inputs (Level 3)    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 0 0
Significant Unobservable Inputs (Level 3) | Mutual funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 0 0
Significant Unobservable Inputs (Level 3) | NJR stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value 0 $ 0
Fair Value Measured at Net Asset Value Per Share    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value $ 181,620,522  
Redemption Notice Period 12 months 12 months
Fair Value Measured at Net Asset Value Per Share | Stable Value Fund    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value $ 25,246,758 $ 26,907,369
Fair Value Measured at Net Asset Value Per Share | Retirement Year Funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Investments, at fair value $ 156,373,764