CONTINGENCIES AND COMMITMENTS - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($) acrefoot entity settlement installment $ / acrefoot	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Nov. 30, 2025 USD ($)
Long-term purchase commitments - other disclosures
Number of claims | settlement	4
Purchased water	$ 252,897	$ 241,201	$ 223,833
Operating lease renewal term	25 years
Finance lease renewal term	25 years
Minimum
Long-term purchase commitments - other disclosures
Operating lease term	1 year
Finance lease term	1 year
Maximum
Long-term purchase commitments - other disclosures
Operating lease term	50 years
Finance lease term	50 years
Supply Commitment | Camino Real
Long-term purchase commitments - other disclosures
Payments for other commitments	$ 43,800	43,800		$ 21,500
Additional payments for other commitments			22,300
Santa Clara Valley Water District
Long-term purchase commitments - other disclosures
Payments to suppliers	16,000	15,200	12,600
Stockton East Water District (SEWD)
Long-term purchase commitments - other disclosures
Payments to suppliers	$ 13,200	$ 14,300	$ 11,500
Kern County Water Agency (Agency)
Long-term purchase commitments - other disclosures
Minimum acre feet of treated water to be purchased per year over life of contract | acrefoot	20,500
Minimum acre feet of treated water to be purchased under prior agreement | acrefoot	11,500
Number of other parties obligated to purchase treated water | entity	3
Minimum acre feet of treated water to be purchased per year by other parties | acrefoot	32,500
Recorded unconditional purchase obligation	$ 82,400
Purchased water	11,800
Water production costs	$ 5,200
Kern County Water Agency (Agency) | Guarantee Type, Other
Long-term purchase commitments - other disclosures
Unrecorded unconditional purchase obligation, minimum quantity required | acrefoot	20,500
3M Company
Long-term purchase commitments - other disclosures
Number of settlement installments | installment	10
Proceeds from legal settlements	$ 34,800
DuPont
Long-term purchase commitments - other disclosures
Proceeds from legal settlements	$ 6,100
Kern County Water Agency (Agency)
Long-term purchase commitments - other disclosures
Total capital facilities charge and treated water charge obligation per acre foot | $ / acrefoot	577.27
Portion of estimated operating cost per acre foot for treated water delivered | $ / acrefoot	34.35
BVRT Utility Holding Company LLC
Long-term purchase commitments - other disclosures
Recorded unconditional purchase obligation					$ 45,000