XML 92 R36.htm IDEA: XBRL DOCUMENT v3.20.1
Stock-Based Compensation (Tables)
 12 Months Ended
Dec. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]  
Summary of Company's Stock Option Activity and Related Information

A summary of the Company’s stock option activity and related information is as follows:

 

 

 

 

 

 

 

Options Outstanding

 

 

 

Shares

Available

for Grant

 

 

Number

of Stock

Options

Outstanding

 

 

Weighted-

Average

Exercise

Price

 

 

Weighted-

Average

Remaining

Contractual Life

(Years)

 

 

Aggregate

Intrinsic

Value

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(In thousands)

 

Balance at December 31, 2018

 

 

1,908,626

 

 

 

11,603,708

 

 

$

6.64

 

 

 

7.6

 

 

$

10,151

 

Additional options authorized

 

 

3,853,280

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Options granted

 

 

(2,652,505

)

 

 

2,652,505

 

 

 

8.13

 

 

 

 

 

 

 

 

 

Options exercised

 

 

—

 

 

 

(2,219,251

)

 

 

4.34

 

 

 

 

 

 

 

 

 

Options cancelled

 

 

871,116

 

 

 

(871,116

)

 

 

7.15

 

 

 

 

 

 

 

 

 

Withheld shares to pay for taxes on vested RSUs

 

 

253,986

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RSUs granted

 

 

(3,356,820

)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RSUs forfeited

 

 

70,732

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Balance at December 31, 2019

 

 

948,415

 

 

 

11,165,846

 

 

$

7.44

 

 

 

7.6

 

 

$

1,907

 

Vested and exercisable at December 31, 2019

 

 

 

 

 

 

5,120,484

 

 

$

6.32

 

 

 

6.2

 

 

$

1,824

 

Vested and expected to vest at December 31, 2019

 

 

 

 

 

 

10,561,531

 

 

$

7.38

 

 

 

7.5

 

 

$

1,899

 
Schedule of Weighted-Average Assumptions Used in Black-Scholes Option-Pricing Model to Estimate Fair Value of Employee Stock Options at Grant Date

The fair value of employee stock options was estimated at the date of grant using a Black-Scholes option-pricing model with the following weighted-average assumptions:

 

 

 

Year Ended December 31,

 

 

 

2019

 

 

2018

 

 

2017

 

Expected term (in years)

 

 

6.0

 

 

 

6.0

 

 

 

5.9

 

Expected volatility (%)

 

60.7%

 

 

60.4%

 

 

66.0%

 

Risk-free interest rate (%)

 

2.4%

 

 

2.8%

 

 

2.1%

 

Expected dividend yield (%)

 

0%

 

 

0%

 

 

0%

 
Summary of RSU Activity (Detail)

A summary of the Company’s RSU activity and related information is as follows:

 

 

RSUs

 

 

 

 

Number of Shares

 

 

Weighted Average Grant Date Fair Value

 

 

Unvested at December 31, 2018

 

 

1,736,234

 

 

$

9.65

 

 

RSUs granted

 

 

3,356,820

 

 

$

3.63

 

 

RSUs vested

 

 

(642,545

)

 

$

9.45

 

 

RSUs forfeited

 

 

(70,732

)

 

$

6.16

 

 

Unvested at December 31, 2019

 

 

4,379,777

 

 

$

5.14

 

 

Vested and unreleased

 

 

116,344

 

 

 

 

 

 

Outstanding at December 31 2019

 

 

4,496,121

 

 

 

 

 

 

 
Summary of Stock-Based Compensation Expense

Total stock-based compensation expense recognized in the Company’s consolidated statements of operations and comprehensive loss is classified as follows (in thousands):

 

 

Year Ended December 31,

 

 

 

2019

 

 

2018

 

 

2017

 

Research and development

 

$

1,603

 

 

$

1,411

 

 

$

952

 

Selling and marketing

 

 

1,300

 

 

 

700

 

 

 

303

 

General and administrative

 

 

16,542

 

 

 

12,058

 

 

 

4,064

 

Total stock-based compensation expense

 

$

19,445

 

 

$

14,169

 

 

$

5,319