| Summary of assets and liabilities measured at fair value on a recurring basis |
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At December 31, 2016
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Level 1
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Level 2
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Level 3
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Fair Value
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|
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Cash equivalents
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|
$
|
21,353
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|
$
|
—
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|
$
|
—
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|
$
|
21,353
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|
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Marketable securities
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|
|
—
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|
|
11,577
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|
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—
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|
|
11,577
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Derivative warrant liability
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|
$
|
—
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|
$
|
1,314
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$
|
—
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|
$
|
1,314
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|
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|
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|
|
|
|
|
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|
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At December 31, 2015
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|
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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
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|
$
|
14,804
|
|
$
|
—
|
|
$
|
—
|
|
$
|
14,804
|
|
|
Marketable securities
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|
|
—
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|
|
5,274
|
|
|
—
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|
|
5,274
|
|
|
Derivative warrant liability
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|
$
|
—
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$
|
1,907
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$
|
—
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$
|
1,907
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