|**Taxes Other Than Income Taxes**            | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|-------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|**Taxes Other Than Income Taxes [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|Taxes Other Than Income Taxes                | Note 11Taxes Other than Income Taxes
		
		The following table provides the 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
|                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|                                             | Property                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
|                                             | Capital stock                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|                                             | Gross receipts, excise and franchise                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
|                                             | Payroll                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|                                             | Other                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|                                             | Total taxes other than income                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            

X- Details**Name:**
                    wtr_TaxesOtherThanIncomeTaxesAbstract**Namespace Prefix:**
                    wtr_**Data Type:**
                    xbrli:stringItemType**Balance Type:**
                    na**Period Type:**
                    duration X- DefinitionUtilities Operating Expenses, Taxes As In Annual Report [Text Block]+ ReferencesNo definition available.+ Details**Name:**
                    wtr_UtilitiesOperatingExpensesTaxesAsInAnnualReportTextBlock**Namespace Prefix:**
                    wtr_**Data Type:**
                    nonnum:textBlockItemType**Balance Type:**
                    na**Period Type:**
                    duration