Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2017

Earnings Per Share [Abstract]

Schedule of computation of basic and diluted earnings per share

Computation of EPS

	First Quarter
	2017		2016
	(in millions)
Basic EPS:
Net income (loss) attributable to AGL	$	317	$	59
Less: Distributed and undistributed income (loss) available to nonvested shareholders	0		1
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	317	$	58
Basic shares	125.3		136.2
Basic EPS	$	2.53	$	0.43
Diluted EPS:
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	317	$	58
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	$	317	$	58
Basic shares	125.3		136.2
Dilutive securities:
Options and restricted stock awards	1.8		0.8
Diluted shares	127.1		137.0
Diluted EPS	$	2.49	$	0.43
Potentially dilutive securities excluded from computation of EPS because of antidilutive effect	0.1		0.8

Schedule of antidilutive securities excluded from computation of earnings per share

Computation of EPS

	First Quarter
	2017		2016
	(in millions)
Basic EPS:
Net income (loss) attributable to AGL	$	317	$	59
Less: Distributed and undistributed income (loss) available to nonvested shareholders	0		1
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	317	$	58
Basic shares	125.3		136.2
Basic EPS	$	2.53	$	0.43
Diluted EPS:
Distributed and undistributed income (loss) available to common shareholders of AGL and subsidiaries, basic	$	317	$	58
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	$	317	$	58
Basic shares	125.3		136.2
Dilutive securities:
Options and restricted stock awards	1.8		0.8
Diluted shares	127.1		137.0
Diluted EPS	$	2.49	$	0.43
Potentially dilutive securities excluded from computation of EPS because of antidilutive effect	0.1		0.8