Net income per share (Tables)

6 Months Ended

Jun. 30, 2019

Schedule of calculation of net income per share

Net income per share was calculated as follows for the periods indicated below:

	Three Months Ended				Six Months Ended
	June 30,				June 30,
(in thousands, except per share data)		2019	2018			2019	2018
Basic Net Income Per Share
Basic net income	$	105,318	$	52,394	$	207,630	$	11,254
Weighted average common shares outstanding		214,620		212,210		214,342		211,945
Basic net income per share	$	0.49	$	0.25	$	0.97	$	0.05
Diluted Net Income Per Share
Diluted net income	$	105,318	$	52,394	$	207,630	$	11,254
Weighted average common shares outstanding		214,620		212,210		214,342		211,945
Dilutive stock options and awards		2,863		2,893		2,932		3,349
Weighted average shares used to compute diluted net income per share		217,483		215,103		217,274		215,294
Diluted net income per share	$	0.48	$	0.24	$	0.96	$	0.05

Schedule of antidilutive securities excluded from the computation of earnings per share

The following potential common shares were excluded from the calculations as their effect would be anti-dilutive:

	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2019	2018	2019	2018
Outstanding stock options and awards	9,165,776	8,079,446	9,221,941	6,732,551
Common shares issuable upon conversion of the 2018 Notes	—	148,817	—	148,817
Common shares issuable upon conversion of the 2020 Notes	368,939	368,939	368,939	368,939
Total potential common shares excluded from diluted net income (loss) per share computation	9,534,715	8,597,202	9,590,880	7,250,307