Military Privatization (Details) - Contracted services: $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($)
Bay State Utility Service LLC ("BSUS")
Military Privatization
Period of fixed price contracts to maintain water systems at various military bases	15 years
Initial price contract value and subject to annual economic price adjustments	$ 75.0
ContractInitialOrderValueToPerformAnEvaluationConstructionAndTransitionServices	4.1
Patuxent River Utility Services LLC("PRUS")
Military Privatization
Initial price contract value and subject to annual economic price adjustments	$ 349.0
Period of Fixed Price Contracts to Operate and Maintain Water Systems at Various Military Bases	50 years
Revised price contract value after an inventory adjustment	$ 378.0
Maximum \| American States Utility Services
Military Privatization
Period of fixed price contracts to maintain water systems at various military bases	50 years
Period of Fixed Price Contracts to Operate and Maintain Water Systems at Various Military Bases	50 years

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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