REGULATORY MATTERS (Regulatory Assets and Liabilities - Footnotes) (Details)	3 Months Ended
Mar. 31, 2026
Roadrunner Reserve I
Regulatory Assets [Line Items]
Investment tax credits, amortization period	5 years
Income Taxes Recoverable (Payable) through Future Rates
Regulatory Assets [Line Items]
Amortization period	10 years

Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_RegulatoryAssetAmortizationPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant