Earnings Per Common Share (Tables)

3 Months Ended

Mar. 31, 2019

Earnings Per Common Share

Schedule of components of basic and diluted earnings per common share

The components of basic and diluted (loss) earnings per common share comprised the following (in millions, except per share amounts):

	Three Months Ended
	March 31,
	2019		2018
Numerator:
Net (loss) income	$	(494.6)	$	244.5
Denominator:
Weighted average outstanding shares - basic		43.7		43.3
Effect of dilutive securities(1):
Stock options, restricted stock units and employee stock purchase plan		—		0.6
Weighted average shares - diluted(2)		43.7		43.9
Net (loss) income per common share:
Basic	$	(11.32)	$	5.65
Diluted	$	(11.32)	$	5.57
Stock options and restricted stock units excluded from calculation(2)		5.3		3.9

(1) Calculated using the treasury stock method.

(2) The common shares underlying certain stock options and restricted stock units have been excluded from the computation of diluted earnings per share because their impact would be anti-dilutive for the three-month periods ended March 31, 2019 and March 31, 2018.