Earnings Per Share

9 Months Ended

Sep. 30, 2017

Earnings Per Share [Abstract]

Earnings Per Share

18. Earnings Per Share

The following table presents the weighted average number of outstanding stock-based awards not included in the computation of diluted earnings per share because they are subject to performance conditions or the effect of including such stock-based awards in the computation would be anti-dilutive:

	Three Months Ended September 30,				Nine Months Ended September 30,
(in millions)	2017		2016		2017		2016
Shares subject to performance conditions		0.5		0.2		0.4		0.2
Shares subject to anti-dilutive stock-based awards		0.6		0.7		1.3		1.2
Total shares excluded from diluted earnings per share		1.1		0.9		1.7		1.4

The vesting of performance units is contingent upon the achievement of certain performance targets. The performance units are not included in diluted earnings per share until the performance targets have been met.  Stock-based awards will have a dilutive effect under the treasury method when the respective period’s average market value of the Company’s common stock exceeds the exercise proceeds.