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Commitments and Contingent Liabilities (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 USD ($) gal l | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Commitments and Contingent Liabilities [Line Items] |  |  |
Average purchase of gallons | l | 47 |  |
Estimated incremental borrowing rate | 4.03% |  |
Operating leases, lease expense | $ | $ 0.8 | $ 0.8 | $ 0.8
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration] | Present Value of Lease Payments |  |
Estimated obligation expenditure | $ | $ 9.6 |  |
Purchase Commitment [Member] |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |
Purchase commitment expiration date of contract | Nov. 30, 2048 |  |
Water Supply [Member] |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |
Average purchase of gallons | gal | 27,000,000 |  |
NJBPU-Regulated Water [Member] |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |
Purchase commitment expiration date of contract | Feb. 27, 2026 |  |
Average purchase of gallons | l | 3 |  |
Treated Water [Member] |  |  |
Commitments and Contingent Liabilities [Line Items] |  |  |
Average purchase of gallons | gal | 75,000,000 |  |

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