|**Taxes Other Than Income Taxes (Tables)**   | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                   
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|**Taxes Other Than Income Taxes [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                  
|Components Of Taxes Other Than Income Taxes  | Three Months EndedMarch 31,2014
				
				2013Property
				
				$
				4,824
				
				$
				6,443Capital stock
				
				
				501
				
				
				534Gross receipts, excise and franchise
				
				
				2,779
				
				
				2,681Payroll
				
				
				2,654
				
				
				2,420Other
				
				
				1,344
				
				
				1,320Total taxes other than income
				
				$
				12,102
				
				$
				13,398
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|                                             | Property                                                                                                                                                                                                                                                                                                                                                                                         
|                                             | Capital stock                                                                                                                                                                                                                                                                                                                                                                                    
|                                             | Gross receipts, excise and franchise                                                                                                                                                                                                                                                                                                                                                             
|                                             | Payroll                                                                                                                                                                                                                                                                                                                                                                                          
|                                             | Other                                                                                                                                                                                                                                                                                                                                                                                            
|                                             | Total taxes other than income                                                                                                                                                                                                                                                                                                                                                                    
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