Net Income Per Share

12 Months Ended

Dec. 31, 2014

Earnings Per Share [Abstract]

Net Income Per Share

Note 3:  Net Income Per Share

The following table reconciles net income and shares used in the calculation of basic net income per share to those used for diluted net income per share:

(in millions)	2014		2013		2012
Numerator:
Net income, as reported, for basic net income per share	$	127.1	$	112.3	$	80.7
Plus: interest expense on convertible debt, net of tax	—		—		2.0
Net income for diluted net income per share	$	127.1	$	112.3	$	82.7
Denominator:
Weighted average common shares outstanding	70.9		69.6		68.1
Dilutive effect of stock options, stock appreciation rights and performance share awards, based on the treasury stock method	1.9		1.7		1.1
Assumed conversion of convertible debt, based on the if-converted method	—		0.1		2.6
Weighted average shares assuming dilution	72.8		71.4		71.8

During 2014 and 2012, there were 0.5 million and 1.0 million shares from stock-based compensation plans not included in the computation of diluted net income per share because their impact was antidilutive. During 2013, the number of shares not included in the computation of diluted net income per share was immaterial.

On October 29, 2014, our Board of Directors authorized the repurchase of up to $100.0 million of our common stock from time to time on the open market or in privately negotiated transactions as permitted under the regulations of the Securities and Exchange Commission. The extent to which we repurchase the shares and the timing of any repurchases will be determined by us based on our evaluation of market conditions and other factors. The program is expected to be completed no later than December 31, 2015. As of December 31, 2014, no shares had been repurchased under the program.