Summary of Significant Accounting Policies (Tables)
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3 Months Ended |
Mar. 31, 2019 |
|---|
| Accounting Policies [Abstract] |
|
| Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis |
The following tables present the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis using the above input categories (in thousands):
|
|
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As of March 31, 2019
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Level 1
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Level 2
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Level 3
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Fair Value
|
|
|
Cash equivalents:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds
|
|
$
|
113,114
|
|
|
$
|
-
|
|
|
$
|
-
|
|
|
$
|
113,114
|
|
|
U.S. commercial paper
|
|
|
-
|
|
|
|
3,481
|
|
|
|
-
|
|
|
|
3,481
|
|
|
Total cash equivalents
|
|
|
113,114
|
|
|
|
3,481
|
|
|
|
-
|
|
|
|
116,595
|
|
|
Marketable securities:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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U.S. and foreign commercial paper
|
|
|
-
|
|
|
|
52,158
|
|
|
|
-
|
|
|
|
52,158
|
|
|
U.S. and foreign corporate debt securities
|
|
|
-
|
|
|
|
38,318
|
|
|
|
-
|
|
|
|
38,318
|
|
|
Asset-backed securities
|
|
|
-
|
|
|
|
25,400
|
|
|
|
-
|
|
|
|
25,400
|
|
|
U.S. treasury securities
|
|
|
-
|
|
|
|
23,306
|
|
|
|
-
|
|
|
|
23,306
|
|
|
Total short-term investments
|
|
|
-
|
|
|
|
139,182
|
|
|
|
-
|
|
|
|
139,182
|
|
|
Total assets measured at fair value
|
|
$
|
113,114
|
|
|
$
|
142,663
|
|
|
$
|
-
|
|
|
$
|
255,777
|
|
|
|
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As of December 31, 2018
|
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Level 1
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|
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Level 2
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|
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Level 3
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Fair Value
|
|
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Cash equivalents:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds
|
|
$
|
39,481
|
|
|
$
|
-
|
|
|
$
|
-
|
|
|
$
|
39,481
|
|
|
U.S. and foreign commercial paper
|
|
|
-
|
|
|
|
6,469
|
|
|
|
-
|
|
|
|
6,469
|
|
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Total cash equivalents
|
|
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39,481
|
|
|
|
6,469
|
|
|
|
-
|
|
|
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45,950
|
|
|
Marketable securities:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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U.S. and foreign commercial paper
|
|
|
-
|
|
|
|
51,627
|
|
|
|
-
|
|
|
|
51,627
|
|
|
U.S. and foreign corporate debt securities
|
|
|
-
|
|
|
|
34,634
|
|
|
|
-
|
|
|
|
34,634
|
|
|
Asset-backed securities
|
|
|
-
|
|
|
|
25,472
|
|
|
|
-
|
|
|
|
25,472
|
|
|
U.S. treasury securities
|
|
|
-
|
|
|
|
17,936
|
|
|
|
-
|
|
|
|
17,936
|
|
|
Total short-term investments
|
|
|
-
|
|
|
|
129,669
|
|
|
|
-
|
|
|
|
129,669
|
|
|
Total assets measured at fair value
|
|
$
|
39,481
|
|
|
$
|
136,138
|
|
|
$
|
-
|
|
|
$
|
175,619
|
|
|
| Schedule of Changes in Fair Value of Liabilities |
The following table sets forth a summary of the changes in the fair value of the Company’s liabilities measured using Level 3 inputs (in thousands):
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|
For the Three
|
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|
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Months Ended March 31,
|
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2019
|
|
|
2018
|
|
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Balance, beginning of period
|
|
$
|
-
|
|
|
$
|
6,091
|
|
|
Change in fair value
|
|
|
-
|
|
|
|
4,654
|
|
|
Settlement of financial instruments
|
|
|
-
|
|
|
|
(3,097
|
)
|
|
Balance, end of period
|
|
$
|
-
|
|
|
$
|
7,648
|
|
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| Schedule of Amortized Cost, Unrealized Gain and Loss, and Fair Value of Available for Sale Marketable Securities |
The following tables summarize amortized cost, unrealized gain and loss, and fair value of the Company’s available for sale marketable securities (in thousands):
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Gross
|
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Gross
|
|
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|
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|
|
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Amortized
|
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Unrealized
|
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Unrealized
|
|
|
Estimated
|
|
|
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Cost
|
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Gains
|
|
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Losses
|
|
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Fair Value
|
|
|
As of March 31, 2019:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. and foreign commercial paper
|
|
$
|
52,158
|
|
|
$
|
-
|
|
|
$
|
-
|
|
|
$
|
52,158
|
|
|
U.S. and foreign corporate debt securities
|
|
|
38,289
|
|
|
|
29
|
|
|
|
-
|
|
|
|
38,318
|
|
|
Asset-backed securities
|
|
|
25,395
|
|
|
|
6
|
|
|
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(1
|
)
|
|
|
25,400
|
|
|
U.S. treasury securities
|
|
|
23,295
|
|
|
|
11
|
|
|
|
-
|
|
|
|
23,306
|
|
|
|
|
$
|
139,137
|
|
|
$
|
46
|
|
|
$
|
(1
|
)
|
|
$
|
139,182
|
|
|
|
|
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|
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Gross
|
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Gross
|
|
|
|
|
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Amortized
|
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Unrealized
|
|
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Unrealized
|
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Estimated
|
|
|
|
|
Cost
|
|
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Gains
|
|
|
Losses
|
|
|
Fair Value
|
|
|
As of December 31, 2018:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. and foreign commercial paper
|
|
$
|
51,627
|
|
|
$
|
-
|
|
|
$
|
-
|
|
|
$
|
51,627
|
|
|
U.S. and foreign corporate debt securities
|
|
|
34,668
|
|
|
|
-
|
|
|
|
(34
|
)
|
|
|
34,634
|
|
|
Asset-backed securities
|
|
|
25,494
|
|
|
|
-
|
|
|
|
(22
|
)
|
|
|
25,472
|
|
|
U.S. treasury securities
|
|
|
17,938
|
|
|
|
-
|
|
|
|
(2
|
)
|
|
|
17,936
|
|
|
|
|
$
|
129,727
|
|
|
$
|
-
|
|
|
$
|
(58
|
)
|
|
$
|
129,669
|
|
|
| Computation of Basic and Diluted Net Loss per Share |
The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts):
|
|
|
Three Months Ended
|
|
|
|
|
March 31,
|
|
|
|
|
2019
|
|
|
2018
|
|
|
Numerator:
|
|
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|
|
|
|
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Net loss allocated to common stock-basic
|
|
$
|
(23,075
|
)
|
|
$
|
(17,005
|
)
|
|
Net loss allocated to common stock-diluted
|
|
$
|
(23,075
|
)
|
|
$
|
(17,005
|
)
|
|
Denominator:
|
|
|
|
|
|
|
|
|
|
Weighted average number of
common stock shares
outstanding - basic
|
|
|
61,890,632
|
|
|
|
53,752,753
|
|
|
Weighted average number of
common stock shares
outstanding - diluted
|
|
|
61,890,632
|
|
|
|
53,752,753
|
|
|
Net loss per share - basic:
|
|
$
|
(0.37
|
)
|
|
$
|
(0.32
|
)
|
|
Net loss per share - diluted:
|
|
$
|
(0.37
|
)
|
|
$
|
(0.32
|
)
|
|
| Anti-Dilutive Securities Excluded from the Computation of Diluted Net Loss per Share |
The following table shows the total outstanding securities considered anti-dilutive and therefore excluded from the computation of diluted net loss per share (in thousands):
|
|
|
Three Months Ended
|
|
|
|
|
March 31,
|
|
|
|
|
2019
|
|
|
2018
|
|
|
Common stock options
|
|
|
7,349
|
|
|
|
5,173
|
|
|
Incentive awards
|
|
|
127
|
|
|
|
130
|
|
|
Common stock warrants
|
|
|
-
|
|
|
|
982
|
|
|
|
|
|
7,476
|
|
|
|
6,285
|
|
|