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v3.22.2

Commitments and Contingent Liabilities (Narrative) (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) gal | Jun. 30, 2021 USD ($)
Purchase Commitment, Excluding Long-Term Commitment [Line Items] |  |  |  |
Construction program | $ |  |  | $ 90.0 |
Estimated obligation expenditure | $ |  |  | 35.0 |
Rental expenses under operating leases | $ | $ 0.2 | $ 0.2 | $ 0.4 | $ 0.4
Estimated incremental borrowing rate | 4.03% |  | 4.03% |
NJ Water Supply Authority [Member] |  |  |  |
Purchase Commitment, Excluding Long-Term Commitment [Line Items] |  |  |  |
Purchase commitment expiration date of contract |  |  | Nov. 30, 2023 |
Water purchase per commitment | gal |  |  | 27 |
Regulated Water Authority [Member] |  |  |  |
Purchase Commitment, Excluding Long-Term Commitment [Line Items] |  |  |  |
Purchase commitment expiration date of contract |  |  | Feb. 27, 2026 |
Water purchase per commitment | gal |  |  | 3 |
City of Dover [Member] |  |  |  |
Purchase Commitment, Excluding Long-Term Commitment [Line Items] |  |  |  |
Water purchase per commitment | gal |  |  | 15 |

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