Net Income (Loss) Per Share Attributable to Common Stockholders (Tables)

12 Months Ended

Dec. 31, 2017

Computation of numerators and denominators of basic and diluted net income (loss) per share attributable to common stockholders

	Year Ended December 31,
	2015			2016			2017
Net income (loss) per share attributable to common stockholders—basic:
Numerator:
Net income	$	15,929		$	20,482		$	50,798
Less: Income attributable to convertible preferred stock		(10,958	)		—			—
Add: Preferred stock modification		3,793			—			—
Less: Premium on repurchase of convertible preferred stock		—			(47,209	)		—
Net income (loss) attributable to common stockholders	$	8,764		$	(26,727	)	$	50,798
Denominator:
Weighted-average shares outstanding		10,290			18,280			40,262
Net income (loss) per share attributable to common stockholders—basic	$	0.85		$	(1.46	)	$	1.26
Net income (loss) per share attributable to common stockholders—diluted:
Numerator:
Net income (loss) attributable to common stockholders—basic	$	8,764		$	(26,727	)	$	50,798
Add: Income attributable to dilutive convertible preferred stock		1,624			—			—
Less: Preferred stock modification		(3,793	)		—			—
Net income (loss) attributable to common stockholders—diluted	$	6,595		$	(26,727	)	$	50,798
Denominator:
Weighted-average shares outstanding		10,290			18,280			40,262
Dilutive convertible preferred stock		2,790			—			—
Options to purchase common stock		3,699						3,415
Employee stock purchase plan shares		—			—			268
Restricted stock		—			—			111
Weighted-average shares outstanding—diluted		16,779			18,280			44,056
Net income (loss) per share attributable to common stockholders—diluted	$	0.39		$	(1.46	)	$	1.15

Schedule of anti-dilutive shares excluded from the calculation of diluted earnings (loss) per share

The following table presents the anti-dilutive shares excluded from the calculation of diluted net income (loss) per share attributable to common stockholders (in thousands):

	Year Ended December 31,
	2015		2016		2017
Anti-dilutive equity awards under stock-based award plans		248		6,069		1,246
Common shares issuable upon conversion of convertible preferred stock		19,320		—		—
Common shares issuable upon conversion of preferred stock warrants		547		—		—
Total shares excluded from net income (loss) per share attributable to common stockholders—diluted		20,115		6,069		1,246