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GOODWILL - Narrative (Details) - USD ($)			12 Months Ended
GOODWILL - Narrative (Details) - USD ($)	Oct. 03, 2022	Oct. 01, 2022	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Line Items]
Impairment loss		$ 0
CMA
Goodwill [Line Items]
Goodwill acquired			$ 51,900,000
CMA Measurement Period Adjustments				$ 9,600,000
The Torrington Water Company (TWC)
Goodwill [Line Items]
Goodwill acquired			44,800,000
New England Service Company (NESC)
Goodwill [Line Items]
Goodwill acquired				21,700,000
CMA Measurement Period Adjustments			500,000
Water Distribution \| CMA
Goodwill [Line Items]
CMA Measurement Period Adjustments			9,600,000	0
Water Distribution \| The Torrington Water Company (TWC)
Goodwill [Line Items]
Goodwill acquired	$ 44,800,000		44,800,000
Water Distribution \| New England Service Company (NESC)
Goodwill [Line Items]
Goodwill acquired			22,200,000	$ 21,700,000
CMA Measurement Period Adjustments			$ 500,000