Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Pay vs Performance Disclosure
Net Income (Loss) Attributable to ALLETE	$ 45.0	$ 85.9	$ 128.7	$ 195.6

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details