Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2024

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

Computation of Earnings Per Share 

	Year Ended December 31,
	2024		2023		2022
	(in millions, except per share amounts)
Basic EPS:
Net income (loss) attributable to AGL	$	376	$	739	124
Less: Distributed and undistributed income (loss) available to nonvested shareholders	3		6		1
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	373	$	733	123
Basic shares	53.3		58.4		62.9
Basic EPS	$	7.01	$	12.54	$	1.95
Diluted EPS:
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	373	$	733	$	123
Plus: Re-allocation of undistributed income (loss) available to nonvested shareholders of AGL and subsidiaries	—		—		—
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, diluted	$	373	$	733	$	123
Basic shares	53.3		58.4		62.9
Dilutive securities:
Restricted stock awards	1.0		1.2		1.0
Diluted shares	54.3		59.6		63.9
Diluted EPS	$	6.87	$	12.30	$	1.92
Potentially dilutive securities excluded from computation of EPS because of antidilutive effect	0.1		0.1		0.6

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

Computation of Earnings Per Share 

	Year Ended December 31,
	2024		2023		2022
	(in millions, except per share amounts)
Basic EPS:
Net income (loss) attributable to AGL	$	376	$	739	124
Less: Distributed and undistributed income (loss) available to nonvested shareholders	3		6		1
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	373	$	733	123
Basic shares	53.3		58.4		62.9
Basic EPS	$	7.01	$	12.54	$	1.95
Diluted EPS:
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	373	$	733	$	123
Plus: Re-allocation of undistributed income (loss) available to nonvested shareholders of AGL and subsidiaries	—		—		—
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, diluted	$	373	$	733	$	123
Basic shares	53.3		58.4		62.9
Dilutive securities:
Restricted stock awards	1.0		1.2		1.0
Diluted shares	54.3		59.6		63.9
Diluted EPS	$	6.87	$	12.30	$	1.92
Potentially dilutive securities excluded from computation of EPS because of antidilutive effect	0.1		0.1		0.6