|**Capitalization**            | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|----------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|**Capitalization [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|Capitalization                | Note 5 –Capitalization
		﻿
		In July 2017, Aqua Illinois issued$100,000of first mortgage bonds consisting of the following:
		﻿
		﻿\Amount
				Interest Rate
				Maturity﻿$25,000
				3.64%
				2032﻿$6,000
				3.89%
				2037﻿$15,000
				3.90%
				2038﻿$10,000
				4.18%
				2047﻿$22,000
				4.22%
				2049﻿$22,000
				4.24%
				2050
		﻿
		The proceeds from these bonds were used to repay existing indebtedness and for general corporate purposes.
		﻿
		In July 2017, Aqua Pennsylvania issued$80,000of first mortgage bonds, of which$40,000is due in2055and$40,000is due in2057with interest rates of4.04%and4.06%, respectively.  The proceeds from these bonds were used to repay existing indebtedness and for general corporate purposes.
		﻿
		In January 2017, Aqua Pennsylvania issued$50,000of first mortgage bonds, of which$10,000is due in2042and$40,000is due in2044with interest rates of3.65%and3.69%, respectively. The proceeds from these bonds were used to repay existing indebtedness and for general corporate purposes.
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|Amount                        | Interest Rate                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
|﻿$25,000                      | 3.64%                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|﻿$6,000                       | 3.89%                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|﻿$15,000                      | 3.90%                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|﻿$10,000                      | 4.18%                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|﻿$22,000                      | 4.22%                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|﻿$22,000                      | 4.24%                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    

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