Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2018

Earnings Per Share [Abstract]

Schedule of computation of basic and diluted earnings per share

Computation of Earnings Per Share

	First Quarter
	2018		2017
	(in millions)
Basic Earnings Per Share (EPS):
Net income (loss) attributable to AGL	$	197	$	317
Less: Distributed and undistributed income (loss) available to nonvested shareholders	1		0
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	196	$	317
Basic shares	115.2		125.3
Basic EPS	$	1.71	$	2.53
Diluted EPS:
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	196	$	317
Plus: Re-allocation of undistributed income (loss) available to nonvested shareholders of AGL and subsidiaries	0		0
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, diluted	$	196	$	317
Basic shares	115.2		125.3
Dilutive securities:
Options and restricted stock awards	1.4		1.8
Diluted shares	116.6		127.1
Diluted EPS	$	1.68	$	2.49
Potentially dilutive securities excluded from computation of EPS because of antidilutive effect	0.2		0.1

Schedule of antidilutive securities excluded from computation of earnings per share

Computation of Earnings Per Share

	First Quarter
	2018		2017
	(in millions)
Basic Earnings Per Share (EPS):
Net income (loss) attributable to AGL	$	197	$	317
Less: Distributed and undistributed income (loss) available to nonvested shareholders	1		0
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	196	$	317
Basic shares	115.2		125.3
Basic EPS	$	1.71	$	2.53
Diluted EPS:
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	196	$	317
Plus: Re-allocation of undistributed income (loss) available to nonvested shareholders of AGL and subsidiaries	0		0
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, diluted	$	196	$	317
Basic shares	115.2		125.3
Dilutive securities:
Options and restricted stock awards	1.4		1.8
Diluted shares	116.6		127.1
Diluted EPS	$	1.68	$	2.49
Potentially dilutive securities excluded from computation of EPS because of antidilutive effect	0.2		0.1