COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)	Apr. 30, 2025 USD ($)
Commitments and Contingencies [Line Items]
Number Of Former Manufactured Gas Sites Where We Own Or Retain Legal Responsibility For Environmental Conditions	12
Number of sites with ongoing groundwater monitoring	7
Number of sites where regulatory closure has been achieved	5
Deferred MGP Costs, Maximum	$ 32,000		$ 15,000
Regulatory Asset for Costs Associated with Manufactured Gas Sites	30,600	$ 30,100
Accrual for Environmental Loss Contingencies	$ 13,200	$ 13,700

[Line Items] for Disclosure of commitments and contingencies [Table]

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Deferred MGP Costs, Maximum

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Number of former manufactured gas sites where we own or retain legal responsibility.

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Number of sites where regulatory closure has been achieved

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Number of sites where groundwater continues to be monitored in accordance to plans approved by the KDHE.

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Regulatory Asset for Costs Associated with Manufactured Gas Sites

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

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