LONG-TERM DEBT (Details) - USD ($) $ in Millions	1 Months Ended
Aug. 31, 2026	Jan. 31, 2026
WPS 4.25% $300M Senior Notes due January 15, 2031
Debt Instrument [Line Items]
Proceeds from issuance of debt		$ 300.0
Debt instrument stated interest rate percentage		4.25%
WPS 6.05% $300M Senior Notes due August 15, 2056
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 300.0
Debt instrument stated interest rate percentage	6.05%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details