| **Discontinued Operations And Other Disposition (Schedule Of Disposal Groups Including Discontinued Operations) (Details) (USD $)In Thousands, unless otherwise specified** | Dec. 31, 2013                                                                                  |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------|
| **Discontinued Operations And Other Disposition [Abstract]**                                                                                                                |                                                                                           |
| Property, plant and equipment, at cost                                                                                                                                      | $ 37,303wtr_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentGross          |
| Less: accumulated depreciation                                                                                                                                              | 8,378wtr_DisposalGroupIncludingDiscontinuedOperationAccumulatedDepreciation                    |
| Net property, plant and equipment                                                                                                                                           | 28,925us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipment             |
| Current assets                                                                                                                                                              | 1,362wtr_DisposalGroupIncludingDiscontinuedOperationCurrentAssets                              |
| Regulatory assets                                                                                                                                                           | 460wtr_DisposalGroupIncludingDiscontinuedOperationRegulatoryAssets                             |
| Assets of discontinued operations held for sale                                                                                                                             | 30,747us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent                       |
| Current liabilities                                                                                                                                                         | 16,212wtr_DisposalGroupIncludingDiscontinuedOperationCurrentLiabilities                        |
| Deferred income taxes and investment tax credits                                                                                                                            | 1,308wtr_DisposalGroupIncludingDiscontinuedOperationDeferredIncomeTaxesAndInvestmentTaxCredits |
| Contributions in aid of construction                                                                                                                                        | 10,935wtr_DisposalGroupIncludingDiscontinuedOperationContributionsInAidOfConstruction          |
| Other liabilities                                                                                                                                                           | 1,194us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities             |
| Liabilities of discontinued operations held for sale                                                                                                                        | 29,649us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent                  |
| Net (liabilities) assets                                                                                                                                                    | $ 1,098wtr_DisposalGroupIncludingDiscontinuedOperationNetAssets                                |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759
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| X                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount classified as other liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of beyond one year or the normal operating cycle, if longer.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760
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| X                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation accumulated depreciation
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation contributions in aid of construction
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation current assets
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation current liabilities
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation deferred income taxes and investment tax credits
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation net assets
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation property, plant and equipment, gross
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation regulatory assets
+ References
No definition available.
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