| Schedule of short-term investments |
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December 31, 2019
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Gross unrealized
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Gross unrealized
|
|
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|
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Amortized cost
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|
gains
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losses
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Fair value
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Commercial paper
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|
$
|
42,148
|
|
$
|
24
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|
$
|
—
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|
$
|
42,172
|
|
US Government agency bonds
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|
|
13,045
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|
|
—
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|
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(9)
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|
|
13,036
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US Treasury bonds
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|
|
28,107
|
|
|
—
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|
|
(2)
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|
|
28,105
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Corporate debt securities
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|
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34,562
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|
5
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|
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(3)
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|
34,564
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|
$
|
117,862
|
|
$
|
29
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|
$
|
(14)
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|
$
|
117,877
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|
|
|
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|
|
|
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|
|
|
|
|
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|
|
March 31, 2019
|
|
|
|
|
|
Gross unrealized
|
|
Gross unrealized
|
|
|
|
|
|
Amortized cost
|
|
gains
|
|
losses
|
|
Fair value
|
|
Commercial paper
|
|
$
|
46,687
|
|
$
|
2
|
|
$
|
(2)
|
|
$
|
46,687
|
|
US Government agency bonds
|
|
|
15,889
|
|
|
4
|
|
|
—
|
|
|
15,893
|
|
US Treasury bonds
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|
|
38,047
|
|
|
13
|
|
|
—
|
|
|
38,060
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Corporate debt securities
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|
|
8,469
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|
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—
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(2)
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|
|
8,467
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|
|
|
$
|
109,092
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|
$
|
19
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|
$
|
(4)
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|
$
|
109,107
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