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v3.20.2

Commitments and Contingent Liabilities (Narrative) (Details) gal in Millions, $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) gal | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($)
Purchase Commitment, Excluding Long-term Commitment [Line Items] |  |  |  |  |
Guaranty liabilty for AWM's performance | $ 1.3 |  | $ 1.3 |  | $ 1.4
Budgeted construction cost for construction program, 2020 |  |  | 113.0 |  |
Contractual construction agreements |  |  | 41.0 |  |
Rental expenses under operating leases | $ 0.2 | $ 0.2 | $ 0.6 | $ 0.5 |
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 |  |  | 27.0 |  |
Regulated Water Authority [Member] |  |  |  |  |
Purchase Commitment, Excluding Long-term Commitment [Line Items] |  |  |  |  |
Purchase commitment expiration date of contract |  |  | Feb. 28, 2026 |  |
Water purchase per commitment | gal |  |  | 3.0 |  |
City of Dover [Member] |  |  |  |  |
Purchase Commitment, Excluding Long-term Commitment [Line Items] |  |  |  |  |
Water purchase per commitment | gal |  |  | 15.0 |  |

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