Net income (loss) per share (Tables)

6 Months Ended

Jun. 30, 2020

Earnings Per Share [Abstract]

Basic and Diluted Net Income per Share

The following table presents the calculation of basic and diluted net income (loss) per share:

	Three Months Ended June 30,					Six Months Ended June 30,
	2020		2019			2020		2019
Numerator:
Net income (loss)	$	92.7	$	(9.5	)	$	80.2	$	(35.6	)
Denominator:
Weighted-average number of shares—basic	52.6		51.5			52.3		51.3
Dilutive securities—equity awards	0.9		—			0.9		—
Weighted-average number of shares—diluted	53.5		51.5			53.2		51.3
Net income (loss) per share - basic	$	1.76	$	(0.18	)	$	1.53	$	(0.69	)
Net income (loss) per share - diluted	$	1.73	$	(0.18	)	$	1.51	$	(0.69	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

The following table presents the share-based awards that are not considered in the diluted net income (loss) per share calculation because the exercise price of the awards was greater than the average per share closing price during the three and six months ended June 30, 2020 and 2019.

	Three Months Ended June 30,		Six Months Ended June 30,
	2020	2019	2020	2019
Anti-dilutive stock awards	0.4	3.0	0.6	3.0