|**Discontinued Operations And Other Disposition (Tables)**                                                 | 3 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 | Three Months EndedMarch 31,2014
				
				2013Operating revenues
				
				$
				1,579
				
				$
				7,493Total operating expenses
				
				
				673
				
				
				5,020Operating income
				
				
				906
				
				
				2,473Other (income) expense:Loss (gain) on sale
				
				
				134
				
				
				(6,451)Other, net
				
				
				-
				
				
				(1)Income from discontinued operations before income taxes
				
				
				772
				
				
				8,925Provision for income taxes
				
				
				314
				
				
				3,224Income from discontinued operations
				
				$
				458
				
				$
				5,701                                                                                                                                                                                                                                                                                                                                 
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|                                                                                                           | Operating revenues                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|                                                                                                           | Total operating expenses                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|                                                                                                           | Operating income                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|                                                                                                           | Other (income) expense:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|                                                                                                           | Loss (gain) on sale                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|                                                                                                           | Other, net                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|                                                                                                           | Income from discontinued operations before income taxes                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|                                                                                                           | Provision for income taxes                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|                                                                                                           | Income from discontinued operations                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Schedule Of Disposal Groups Including Discontinued Operations                                              | March 31,
				
				December 31,2014
				
				2013Property, plant and equipment, at cost
				
				$
				39,747
				
				$
				39,976Less: accumulated depreciation
				
				
				8,753
				
				
				8,872Net property, plant and equipment
				
				
				30,994
				
				
				31,104Current assets
				
				
				814
				
				
				1,362Regulatory assets
				
				
				442
				
				
				460Assets of discontinued operations held for sale
				
				
				32,250
				
				
				32,926Current liabilities
				
				
				15,209
				
				
				16,212Deferred income taxes and investment tax credits
				
				
				1,725
				
				
				1,308Contributions in aid of construction
				
				
				10,935
				
				
				10,935Other liabilities
				
				
				1,168
				
				
				1,194Liabilities of discontinued operations held for sale
				
				
				29,037
				
				
				29,649Net assets
				
				$
				3,213
				
				$
				3,277
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|                                                                                                           | Property, plant and equipment, at cost                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|                                                                                                           | Less: accumulated depreciation                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|                                                                                                           | Net property, plant and equipment                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
|                                                                                                           | Current assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|                                                                                                           | Regulatory assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
|                                                                                                           | Assets of discontinued operations held for sale                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
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|                                                                                                           | Current liabilities                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|                                                                                                           | Deferred income taxes and investment tax credits                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|                                                                                                           | Contributions in aid of construction                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|                                                                                                           | Other liabilities                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
|                                                                                                           | Liabilities of discontinued operations held for sale                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
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|                                                                                                           | Net assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
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