| **Discontinued Operations And Other Disposition (Schedule Of Disposal Groups Including Discontinued Operations) (Details) (USD $)In Thousands, unless otherwise specified** | Mar. 31, 2014 | Dec. 31, 2013 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Discontinued Operations And Other Disposition [Abstract]**                                                                                                                |          |          |
| Property, plant and equipment, at cost                                                                                                                                      | $ 39,747      | $ 39,976      |
| Less: accumulated depreciation                                                                                                                                              | 8,753         | 8,872         |
| Net property, plant and equipment                                                                                                                                           | 30,994        | 31,104        |
| Current assets                                                                                                                                                              | 814           | 1,362         |
| Regulatory assets                                                                                                                                                           | 442           | 460           |
| Assets of discontinued operations held for sale                                                                                                                             | 32,250        | 32,926        |
| Current liabilities                                                                                                                                                         | 15,209        | 16,212        |
| Deferred income taxes and investment tax credits                                                                                                                            | 1,725         | 1,308         |
| Contributions in aid of construction                                                                                                                                        | 10,935        | 10,935        |
| Other liabilities                                                                                                                                                           | 1,168         | 1,194         |
| Liabilities of discontinued operations held for sale                                                                                                                        | 29,037        | 29,649        |
| Net assets                                                                                                                                                                  | $ 3,213       | $ 3,277       |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for current assets (assets with expected useful life shorter than one year or one operating cycle, whichever is longer) of a disposal group, including a component of the entity (discontinued operation), to be sold or that has subsequently been disposed of through sale, as of the financial statement date.
+ References
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| - Definition
For the disposal group, including a component of the entity (discontinued operation), obligations not otherwise itemized that are due after one year or operating cycle, if longer, from the balance sheet date.
+ References
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| - Definition
For the disposal group, including a component of the entity (discontinued operation), carrying value (net of accumulated depreciation and any write-downs) of tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying value as of the balance sheet date of current obligations (due less than one year or one operating cycle, if longer) arising from the sale, disposal or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).
+ References
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Disposal group including discontinued operation accumulated depreciation
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation contributions in aid of construction
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No definition available.
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Disposal group including discontinued operation current liabilities
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Disposal group including discontinued operation deferred income taxes and investment tax credits
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No definition available.
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| X                                                                                                                                                                                                                                                                                                  |
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| - Definition
Disposal group including discontinued operation net assets
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Disposal group including discontinued operation property, plant and equipment, gross
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                |
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| - Definition
Disposal group including discontinued operation regulatory assets
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No definition available.
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