| **Employee Stock And Incentive Plan (Schedule Of Performance Goals) (Details) - Performance Share Units [Member]** | 12 Months Ended |
|--------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                                 |            |   |
| Metric 1                                                                                                           | 25.00%          | 26.47% |
| Metric 2                                                                                                           | 25.00%          | 26.47% |
| Metric 3                                                                                                           | 25.00%          | 23.53% |
| Metric 4                                                                                                           | 25.00%          | 23.53% |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
+ Details**Name:**us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share Based Compensation, Performance Goals, Metrics 1
+ References
No definition available.
+ Details**Name:**wtrg_ShareBasedCompensationPerformanceGoalsMetrics1**Namespace Prefix:**wtrg_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share Based Compensation, Performance Goals, Metrics 2
+ References
No definition available.
+ Details**Name:**wtrg_ShareBasedCompensationPerformanceGoalsMetrics2**Namespace Prefix:**wtrg_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share Based Compensation, Performance Goals, Metrics 3
+ References
No definition available.
+ Details**Name:**wtrg_ShareBasedCompensationPerformanceGoalsMetrics3**Namespace Prefix:**wtrg_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share Based Compensation, Performance Goals, Metrics 4
+ References
No definition available.
+ Details**Name:**wtrg_ShareBasedCompensationPerformanceGoalsMetrics4**Namespace Prefix:**wtrg_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_AwardTypeAxis=wtrg_PerformanceShareUnitsMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |