Earnings Per Share and Common Stock (Tables)

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Reconciliation of Basic and Diluted Earnings Per Share

The difference between basic and diluted earnings per share, if any, arises from non-vested restricted stock units and performance share awards granted under our Executive Long-Term Incentive Compensation Plan.

		2023			2022
Reconciliation of Basic and Diluted		Dilutive			Dilutive
Earnings Per Share	Basic	Securities	Diluted	Basic	Securities	Diluted
Millions Except Per Share Amounts
Quarter ended September 30,
Net Income Attributable to ALLETE	$85.9		$85.9	$33.7		$33.7
Average Common Shares	57.4	0.1	57.5	57.1	0.1	57.2
Earnings Per Share	$1.50		$1.49	$0.59		$0.59
Nine Months Ended September 30,
Net Income Attributable to ALLETE	$195.6		$195.6	$137.6		$137.6
Average Common Shares	57.3	0.1	57.4	55.5	0.1	55.6
Earnings Per Share	$3.41		$3.41	$2.48		$2.48