| Schedule of investments by security type |
Investments by security type consisted of the following (in thousands):
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|
|
|
|
|
|
|
|
|
|
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|
|
|
|
September 30, 2019
|
|
|
|
Amortized Cost
|
|
Gross Unrealized Gains
|
|
Gross Unrealized Losses
|
|
Fair Value
|
|
U.S. treasury bills and notes (due within one year)
|
|
$
|
201,045
|
|
$
|
165
|
|
$
|
(8)
|
|
$
|
201,202
|
|
U.S. government agency bonds (due within one year)
|
|
|
13,867
|
|
|
9
|
|
|
—
|
|
|
13,876
|
|
|
|
$
|
214,912
|
|
$
|
174
|
|
$
|
(8)
|
|
$
|
215,078
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
December 31, 2018
|
|
|
|
Amortized Cost
|
|
Gross Unrealized Gains
|
|
Gross Unrealized Losses
|
|
Fair Value
|
|
U.S. treasury notes (due within one year)
|
|
$
|
79,312
|
|
$
|
—
|
|
$
|
(26)
|
|
$
|
79,286
|
|
U.S. government agency bonds (due within one year)
|
|
|
17,704
|
|
|
—
|
|
|
(3)
|
|
|
17,701
|
|
|
|
$
|
97,016
|
|
$
|
—
|
|
$
|
(29)
|
|
$
|
96,987
|
|
| Schedule of financial assets and liabilities measured at fair value on a recurring basis |
The following tables present the Company’s fair value hierarchy for its assets and liabilities, which are measured at fair value on a recurring basis (in thousands):
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
Fair value measurements at September 30, 2019 using:
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Level 1
|
|
Level 2
|
|
Level 3
|
|
Total
|
|
Assets:
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|
|
|
|
|
|
|
|
|
|
|
|
|
Cash equivalents:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds
|
|
$
|
109,611
|
|
$
|
—
|
|
$
|
—
|
|
$
|
109,611
|
|
Investments:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. government agency bonds
|
|
|
—
|
|
|
13,876
|
|
|
—
|
|
|
13,876
|
|
U.S. treasury bills and notes
|
|
|
—
|
|
|
201,202
|
|
|
—
|
|
|
201,202
|
|
|
|
$
|
109,611
|
|
$
|
215,078
|
|
$
|
—
|
|
$
|
324,689
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Fair value measurements at December 31, 2018 using:
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Level 1
|
|
Level 2
|
|
Level 3
|
|
Total
|
|
Assets:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Cash equivalents:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds
|
|
$
|
282,160
|
|
$
|
—
|
|
$
|
—
|
|
$
|
282,160
|
|
U.S. treasury bills
|
|
|
—
|
|
|
24,904
|
|
|
—
|
|
|
24,904
|
|
Investments:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. government agency bonds
|
|
|
—
|
|
|
17,701
|
|
|
—
|
|
|
17,701
|
|
U.S. treasury notes
|
|
|
—
|
|
|
79,286
|
|
|
—
|
|
|
79,286
|
|
|
|
$
|
282,160
|
|
$
|
121,891
|
|
$
|
—
|
|
$
|
404,051
|
|