| **Consolidated Statements Of Capitalization (Parenthetical) (USD $)** | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended | 3 Months Ended | 12 Months Ended |
|-----------------------------------------------------------------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|----------------|-----------------|
||
| Interest rate                                                         |           |            |           |            |           |            |           |            |           |            |           |            |           |            |           |            |           |            |           |            | 10.40%         | 10.40%          | 3.57%          | 3.57%           |           |            |           |            |
| Interest rate range, minimum                                          | 0.00%          | 0.00%           | 1.00%          | 1.00%           | 2.00%          | 2.00%           | 3.00%          | 3.00%           | 4.00%          | 4.00%           | 5.00%          | 5.00%           | 6.00%          | 6.00%           | 7.00%          | 7.00%           | 8.00%          | 8.00%           | 9.00%          | 9.00%           |           |            |           |            | 4.62%          | 4.62%           | 5.01%          | 5.01%           |
| Interest rate range, maximum                                          | 0.99%          | 0.99%           | 1.99%          | 1.99%           | 2.99%          | 2.99%           | 3.99%          | 3.99%           | 4.99%          | 4.99%           | 5.99%          | 5.99%           | 6.99%          | 6.99%           | 7.99%          | 7.99%           | 8.99%          | 8.99%           | 9.99%          | 9.99%           |           |            |           |            | 4.87%          | 4.87%           | 5.95%          | 5.95%           |
| Maturity date range, start                                            | 2023           | 2023            | 2014           | 2014            | 2024           | 2024            | 2016           | 2016            | 2020           | 2020            | 2015           | 2015            | 2015           | 2015            | 2022           | 2022            | 2021           | 2021            | 2018           | 2018            |           |            |           |            | 2014           | 2014            | 2015           | 2015            |
| Maturity date range, end                                              | 2033           | 2033            | 2035           | 2035            | 2031           | 2031            | 2047           | 2047            | 2048           | 2048            | 2043           | 2043            | 2036           | 2036            | 2027           | 2027            | 2025           | 2025            | 2026           | 2026            |           |            |           |            | 2024           | 2024            | 2037           | 2037            |
| Maturity date                                                         |           |            |           |            |           |            |           |            |           |            |           |            |           |            |           |            |           |            |           |            | 2018           | 2018            | 2027           | 2027            |           |            |           |            |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Contractual interest rate for funds borrowed, under the debt agreement.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Maximum contractual interest rate for funds borrowed, under the debt agreement.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
+ Details**Name:**us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum**Namespace Prefix:**us-gaap_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Minimum contractual interest rate for funds borrowed, under the debt agreement.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
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| X                                                                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Debt Instrument Maturity Date End
+ References
No definition available.
+ Details**Name:**wtr_DebtInstrumentMaturityDateEnd**Namespace Prefix:**wtr_**Data Type:**xbrli:gYearItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Debt Instrument Maturity Date Start
+ References
No definition available.
+ Details**Name:**wtr_DebtInstrumentMaturityDateStart**Namespace Prefix:**wtr_**Data Type:**xbrli:gYearItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Debt Instrument, Maturity Date, Year
+ References
No definition available.
+ Details**Name:**wtr_DebtInstrumentMaturityDateYear**Namespace Prefix:**wtr_**Data Type:**xbrli:gYearItemType**Balance Type:**na**Period Type:**duration |