| **Capitalization (Details) - USD ($)**                                                                           | 1 Months Ended | 6 Months Ended  |
|------------------------------------------------------------------------------------------------------------------|----------------|-----------------|
||
| Facility Due In February 2021 [Member] | Unsecured Credit Facility [Member]                                      |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Maturity                                                                                                         |           | Feb. 28,  2021  |
| Borrowing capacity                                                                                               |           | $ 250,000,000   |
| Facility Due In June 2023 [Member] | Unsecured Credit Facility [Member]                                          |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Maturity                                                                                                         |           | Jun.  01,  2023 |
| Borrowing capacity                                                                                               |           | $ 500,000,000   |
| Aqua Pennsylvania, Inc [Member] | First Mortgage Bonds [Member]                                                  |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Face Amount                                                                                                      |           | $ 100,000,000   |
| Aqua Pennsylvania, Inc [Member] | First Mortgage Bonds Due In 2042 [Member]                                      |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Maturity                                                                                                         |           | Dec. 31,  2042  |
| Face Amount                                                                                                      |           | $ 25,000,000    |
| Interest Rate                                                                                                    |           | 3.99%           |
| Aqua Pennsylvania, Inc [Member] | First Mortgage Bonds Due In 2045 [Member]                                      |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Maturity                                                                                                         |           | Dec. 31,  2045  |
| Face Amount                                                                                                      |           | $ 10,000,000    |
| Interest Rate                                                                                                    |           | 4.04%           |
| Aqua Pennsylvania, Inc [Member] | First Mortgage Bonds Due In 2048 [Member]                                      |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Maturity                                                                                                         |           | Dec. 31,  2048  |
| Face Amount                                                                                                      |           | $ 65,000,000    |
| Interest Rate                                                                                                    |           | 4.09%           |
| Aqua Pennsylvania, Inc [Member] | Tax-Exempt Bond [Member] | Subsequent Event [Member] | Bonds [Member]          |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Debt redeemed                                                                                                    | $ 49,660,000   |            |
| Redemption percentage                                                                                            | 5.25%          |            |
| Aqua Pennsylvania, Inc [Member] | Tax-Exempt Bond [Member] | Subsequent Event [Member] | Bonds Due 2042 [Member] |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Original maturity                                                                                                | 2042           |            |
| Aqua Pennsylvania, Inc [Member] | Tax-Exempt Bond [Member] | Subsequent Event [Member] | Bonds Due 2043 [Member] |           |            |
| **Debt Instrument [Line Items]**                                                                                 |           |            |
| Original maturity                                                                                                | 2043           |            |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Year the original debt was scheduled to mature, in CCYY format.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Face (par) amount of debt instrument at time of issuance.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Contractual interest rate for funds borrowed, under the debt agreement.
+ References
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| 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.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.
+ References
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| X                                                                                                                                                    |
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| X                                                                                                                                                      |
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