Rate Activity (Details) - USD ($)			6 Months Ended
	May 24, 2019	Apr. 24, 2019	Jun. 30, 2020
Water And Wastewater Rates [Line Items]
Base rate increase (decrease)		$ 76,493,000
Base rate increase designed to increase total operating revenues on an annual basis		$ 29,493,000
Increase in water and waster rates		7.50%
Distribution system improvement charges reset level upon new base rates		$ 0
Indiana And Ohio [Member]
Water And Wastewater Rates [Line Items]
Base rate increase (decrease)			$ 1,054,000
Illinois And North Carolina [Member]
Water And Wastewater Rates [Line Items]
Base rate increase (decrease)			$ 4,254,000
Pennsylvania [Member]
Water And Wastewater Rates [Line Items]
Base rate increase (decrease)	$ 47,000,000