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Accrual for Environmental Loss Contingencies, Number Of States Contributed To Downwind Challenges in Maintaining Ozone NAAQS

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- Definition

Accrual for Environmental Loss Contingencies, Number Of States Restricted On Certain Industrial Sources

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- Definition

Accrual for Environmental Loss Contingencies, Number Of States Restricted On Fossil-Fuel Fired Power Plants

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- Definition

Accrual for Environmental Loss Contingencies, Number States Is In EPA Stay

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- Definition

Environmental Remediation Liability

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Expected Period for Costs of Compliance

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Best estimate of the loss exposure for reasonably possible environmental contingencies at an individual site for which no accrual has been recorded.

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Commitments, Guarantees and Contingencies - Environmental Matters (Details) $ in Millions		12 Months Ended
	May 08, 2024 USD ($)	Dec. 31, 2024 USD ($)	Nov. 06, 2024 state	Sep. 29, 2023 state	Jun. 05, 2023 state
Environmental Matters [Line Items]
Number of states contributed to downwind states’ challenges in attaining or maintaining ozone NAAQS					23
Number of states restrictions on fossil-fuel fired power plants					22
Number of states restricted on certain industrial sources					20
Number of remaining covered states			10
States were EPA issued an updated final interim rule addressing the stays				5
Coal Combustion Residuals \| Minnesota Power
Environmental Matters [Line Items]
Expected period for costs of compliance	10 years	12 years
Coal Combustion Residuals \| Minimum \| Minnesota Power
Environmental Matters [Line Items]
Estimated costs of compliance \| $	$ 50.0	$ 65.0
Coal Combustion Residuals \| Maximum \| Minnesota Power
Environmental Matters [Line Items]
Estimated costs of compliance \| $	$ 85.0	120.0
Manufactured Gas Plant \| SWL&P \| Superior, WI
Environmental Matters [Line Items]
Environmental remediation liability \| $		$ 0.3