| **Water And Wastewater Rates (Details) - USD ($) $ in Thousands** | 6 Months Ended | 12 Months Ended |
|-------------------------------------------------------------------|----------------|-----------------|
||
| **Water And Wastewater Rates [Line Items]**                       |           |            |
| Corporate federal income tax rate                                 | 21.00%         | 35.00%          |
| Illinois And Ohio [Member]                                        |           |            |
| **Water And Wastewater Rates [Line Items]**                       |           |            |
| Base rate increase (decrease)                                     | $ 8,640        |            |
| Pennsylvania, North Carolina, And New Jersey [Member]             |           |            |
| **Water And Wastewater Rates [Line Items]**                       |           |            |
| Infrastructure rehabilitation surcharges                          | 19,343         |            |
| Texas, New Jersey, Ohio, And Indiana [Member]                     |           |            |
| **Water And Wastewater Rates [Line Items]**                       |           |            |
| Base rate increase (decrease)                                     | (7,959)        |            |
| Virginia [Member] | Revenue Subject to Refund [Member]            |           |            |
| **Water And Wastewater Rates [Line Items]**                       |           |            |
| Billed revenue                                                    | $ 183          |            |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Percentage of domestic federal statutory tax rate applicable to pretax income (loss).
+ References
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| X                                                                                                                                                                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of public utility's approved rate increase (decrease) by regulatory agency.
+ References
No definition available.
+ Details**Name:**us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.
+ References
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| X                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Infrastructure Rehabilitation Surcharges
+ References
No definition available.
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| X                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Water And Wastewater Rates [Line Items]
+ References
No definition available.
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| X                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------|
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