| **Acquisitions (Details) $ in Thousands**                                                         | 1 Months Ended | 6 Months Ended | 12 Months Ended |
|---------------------------------------------------------------------------------------------------|----------------|----------------|-----------------|
||
| **Business Acquisition [Line Items]**                                                             |           |           |            |   |
| Goodwill                                                                                          |           | $ 42,050       |            | $ 42,230 |
| Water And Wastewater Utility Systems [Member]                                                     |           |           |            |   |
| **Business Acquisition [Line Items]**                                                             |           |           |            |   |
| Number of acquisitions | item                                                                     |           | 3              |            |   |
| Number of customers | customer                                                                    |           | 448            |            | 1,003 |
| Total purchase price                                                                              |           | $ 190          |            | $ 5,860 |
| Goodwill                                                                                          |           |           |            | $ 72 |
| Scenario, Forecast [Member] | Water And Wastewater Utility Systems [Member]                       |           |           |            |   |
| **Business Acquisition [Line Items]**                                                             |           |           |            |   |
| Number of customers | customer                                                                    |           |           | 16,750          |   |
| Number of states company operates in | state                                                      |           |           | 2               |   |
| Subsequent Event [Member] | Water And Wastewater Utility Systems [Member]                         |           |           |            |   |
| **Business Acquisition [Line Items]**                                                             |           |           |            |   |
| Number of acquisitions | item                                                                     | 7              |           |            |   |
| Total purchase price                                                                              | $ 152,800      |           |            |   |
| Subsequent Event [Member] | Illinois [Member] | Water And Wastewater Utility Systems [Member]     |           |           |            |   |
| **Business Acquisition [Line Items]**                                                             |           |           |            |   |
| Number of customers | customer                                                                    | 3,800          |           |            |   |
| Total purchase price                                                                              | $ 25,000       |           |            |   |
| Subsequent Event [Member] | Pennsylvania [Member] | Water And Wastewater Utility Systems [Member] |           |           |            |   |
| **Business Acquisition [Line Items]**                                                             |           |           |            |   |
| Number of customers | customer                                                                    | 5,400          |           |            |   |
| Total purchase price                                                                              | $ 75,100       |           |            |   |
| Subsequent Event [Member] | Pennsylvania [Member] | Wastewater Utility System [Member]            |           |           |            |   |
| **Business Acquisition [Line Items]**                                                             |           |           |            |   |
| Number of customers | customer                                                                    | 10,500         |           |            |   |
| Total purchase price                                                                              | $ 50,250       |           |            |   |

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| - Definition
Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.
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| - Definition
Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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