XML 31 R21.htm IDEA: XBRL DOCUMENT
v3.20.2

Cash, Cash Equivalents and Short-Term Investments (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2020
Cash, Cash Equivalents and Short-Term Investments |
Schedule of Securities Classified as Cash, Cash Equivalents and Short-Term Investments | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | September 30, 2020
​ | ​ | ​ | ​ | Gross Unrealized | ​ | ​ | ​
​ |  | Amortized Cost |  | Gains |  | Losses |  | Fair Value
Cash and cash equivalents: |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |
Money market funds | ​ | $ | 83,011 | ​ | $ | — | ​ | $ | — | ​ | $ | 83,011
Commercial paper | ​ |  | 6,499 | ​ |  | — | ​ |  | — | ​ |  | 6,499
Cash | ​ | ​ | 1,499 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 1,499
Total cash and cash equivalents | ​ | ​ | 91,009 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 91,009
Short-term investments | ​ |  |  | ​ |  |  | ​ |  | ​ | ​ |  |
Commercial paper | ​ | $ | 41,625 | ​ | $ | 30 | ​ | $ | (1) | ​ | $ | 41,654
Corporate bonds | ​ | ​ | 39,219 | ​ | ​ | 58 | ​ | ​ | (3) | ​ | ​ | 39,274
U.S. government-sponsored agency bonds | ​ | ​ | 9,334 | ​ | ​ | 3 | ​ | ​ | — | ​ | ​ | 9,337
Asset-backed securities | ​ |  | 3,221 | ​ |  | 2 | ​ |  | — | ​ |  | 3,223
U.S. treasury notes | ​ |  | 999 | ​ |  | 1 | ​ |  | — | ​ |  | 1,000
Total short-term investments | ​ | ​ | 94,398 | ​ | ​ | 94 | ​ | ​ | (4) | ​ | ​ | 94,488
Total cash equivalents and short-term investments | ​ | $ | 185,407 | ​ | $ | 94 | ​ | $ | (4) | ​ | $ | 185,497
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, 2019
​ | ​ | ​ | ​ | Gross Unrealized | ​ | ​ | ​
​ |  | Amortized Cost |  | Gains |  | Losses |  | Fair Value
Cash and cash equivalents: |  | ​ |  |  | ​ |  |  | ​ |  |  | ​ |
Money market funds | ​ | $ | 147,208 | ​ | $ | — | ​ | $ | — | ​ | $ | 147,208
Commercial paper | ​ |  | 19,357 | ​ |  | 3 | ​ |  | — | ​ |  | 19,360
Corporate bonds | ​ |  | 11,441 | ​ |  | — | ​ |  | — | ​ |  | 11,441
Cash | ​ |  | 3,124 | ​ |  | — | ​ |  | — | ​ |  | 3,124
Total cash and cash equivalents | ​ | ​ | 181,130 | ​ | ​ | 3 | ​ | ​ | — | ​ | ​ | 181,133
Short-term investments | ​ |  |  | ​ |  |  | ​ |  | ​ | ​ |  |
Commercial paper | ​ | $ | 36,667 | ​ | $ | 14 | ​ | $ | — | ​ | $ | 36,681
Corporate bonds | ​ |  | 21,690 | ​ |  | 6 | ​ |  | (3) | ​ |  | 21,693
Asset-backed securities | ​ |  | 8,005 | ​ |  | — | ​ |  | — | ​ |  | 8,005
Total short-term investments | ​ | ​ | 66,362 | ​ | ​ | 20 | ​ | ​ | (3) | ​ | ​ | 66,379
Total cash equivalents and short-term investments | ​ | $ | 247,492 | ​ | $ | 23 | ​ | $ | (3) | ​ | $ | 247,512

X
- References No definition available. + Details
Name: | us-gaap_CashAndCashEquivalentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of cash, cash equivalents, and investments. + References No definition available. + Details
Name: | us-gaap_ScheduleOfCashCashEquivalentsAndShortTermInvestmentsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration