Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Pay vs Performance Disclosure
Net Income (Loss) Attributable to ALLETE	$ 85.9	$ 33.7	$ 195.6	$ 137.6

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

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+ Details