Net Income Per Common Share (Tables)

12 Months Ended

Dec. 31, 2015

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,
	2015		2014		2013
Numerator:
Net income—basic and diluted	$	634	$	525	$	517
Denominator:
Basic weighted-average common shares outstanding	164.0		163.5		163.5
Effect of share-based awards:
Stock options	1.0		1.0		1.2
Nonvested shares	0.6		0.6		0.7
Diluted weighted-average shares	165.6		165.1		165.4
Earnings per share:
Basic	$	3.87	$	3.21	$	3.16
Diluted	3.83		3.18		3.12
Number of anti-dilutive share-based awards	0.4		0.7		0.4