| **Summary Of Significant Accounting Policies (Summary Of Changes In Goodwill) (Details) - USD ($) $ in Thousands** | 12 Months Ended |
|--------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Goodwill [Line Items]**                                                                                          |            |   |
| Balance                                                                                                            | $ 42,230        | $ 42,208 |
| Goodwill acquired                                                                                                  | 10,790          | 72 |
| Reclassifications to utility plant acquisition adjustment                                                          | (139)           | (50) |
| Other                                                                                                              | (155)           |   |
| Balance                                                                                                            | 52,726          | 42,230 |
| Other Segment [Member]                                                                                             |            |   |
| **Goodwill [Line Items]**                                                                                          |            |   |
| Balance                                                                                                            | 4,841           | 4,841 |
| Goodwill acquired                                                                                                  |                 |  |
| Reclassifications to utility plant acquisition adjustment                                                          |                 |  |
| Other                                                                                                              |                 |   |
| Balance                                                                                                            | 4,841           | 4,841 |
| Regulated [Member]                                                                                                 |            |   |
| **Goodwill [Line Items]**                                                                                          |            |   |
| Balance                                                                                                            | 37,389          | 37,367 |
| Goodwill acquired                                                                                                  | 10,790          | 72 |
| Reclassifications to utility plant acquisition adjustment                                                          | (139)           | (50) |
| Other                                                                                                              | (155)           |   |
| Balance                                                                                                            | $ 47,885        | $ 37,389 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.
+ 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
Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
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| X                                                                                                                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Reclassification Of Goodwill, Acquisition Adjustment
+ References
No definition available.
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