| **Discontinued Operations And Other Disposition (Tables)**                                                 | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Discontinued Operations And Other Disposition [Abstract]**                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Summary Of Discontinued Operations Presented In Consolidated Statements Of Income And Comprehensive Income |  

						 

						 

						 

						 

						 

						 

 

						 

						 

						 

						 

						 

						 

 

Years Ended December 31,

 

						 

2014

						 

2013

						 

2012

Operating revenues

$
6,324 				
$
19,014 				
$
38,533 				
Total operating expenses

						 
3,262 				
						 
11,880 				
						 
27,450 				
Operating income

						 
3,062 				
						 
7,134 				
						 
11,083 				
Other (income) expense:

						 

						 

						 

						 

						 

						 

Gain on sale

						 
(29,093)				
						 
(21,178)				
						 
(14,718)				
Other, net

						 

  -

						 
1 				
						 
1,397 				
Income from discontinued operations before income taxes

						 
32,155 				
						 
28,311 				
						 
24,404 				
Provision for income taxes

						 
12,800 				
						 
9,882 				
						 
9,678 				
Income from discontinued operations

$
19,355 				
$
18,429 				
$
14,726 				
  |
| Schedule Of Disposal Groups Including Discontinued Operations                                              |  

						 

						 

 

						 

						 

 

December 31,

 

						 

2013

Property, plant and equipment, at cost

$
37,303 				
Less: accumulated depreciation

						 
8,378 				
Net property, plant and equipment

						 
28,925 				
Current assets

						 
1,362 				
Regulatory assets

						 
460 				
Assets of discontinued operations held for sale

						 
30,747 				
 

						 

						 

Current liabilities

						 
16,212 				
Deferred income taxes and investment tax credits

						 
1,308 				
Contributions in aid of construction

						 
10,935 				
Other liabilities

						 
1,194 				
Liabilities of discontinued operations held for sale

						 
29,649 				
 

						 

						 

Net assets

$
1,098 				
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| - Definition
Tabular disclosure of disposal groups, which may include the gain (loss) recognized in the income statement and the income statement caption that includes that gain (loss), amounts of revenues and pretax profit or loss reported in discontinued operations, the classification and carrying value of the assets and liabilities comprising the disposal group, and the segment in which the disposal group was reported. Also may include the amount of adjustments to amounts previously reported in discontinued operations such as resolution of contingencies arising from the disposal transaction or the operations of the component prior to disposal.
+ References
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| - Definition
Schedule Of Disposal Groups Including Discontinued Operations Income Statement Disclosures [Table Text Block]
+ References
No definition available.
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