Net Income Per Common Share (Tables)

12 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

Calculations For Basic And Diluted Earnings Per Share

The table shows calculations for basic and diluted earnings per share:

(In millions except per share data)	Years ended December 31,
	2016		2015		2014
Numerator:
Net income—basic and diluted	$	591	$	634	$	525
Denominator:
Basic weighted-average common shares outstanding	164.5		164.0		163.5
Effect of share-based awards:
Stock options	1.1		1.0		1.0
Nonvested shares	0.9		0.6		0.6
Diluted weighted-average shares	166.5		165.6		165.1
Earnings per share:
Basic	$	3.59	$	3.87	$	3.21
Diluted	3.55		3.83		3.18
Number of anti-dilutive share-based awards	0.3		0.4		0.7