XML 40 R23.htm IDEA: XBRL DOCUMENT
v3.20.1

Short-term Investments (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2019
Investments Debt And Equity Securities [Abstract] |
Held-to-maturity Securities | The following table summarizes the held-to-maturity securities held at December 31, 2019 and 2018 (in thousands):
|  | Amortized Cost |  |  | Unrealized Gains |  |  | Unrealized Losses |  |  | Fair Value |
As of December 31, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. government securities |  | $ | 1,996 |  |  | $ | 15 |  |  | $ | (14 | ) |  | $ | 1,997 |
Commercial paper |  |  | 998 |  |  |  | — |  |  |  | — |  |  |  | 998 |
Overnight repurchase agreement |  |  | 3,500 |  |  |  | — |  |  |  | — |  |  |  | 3,500 |
Total short-term investments |  | $ | 6,494 |  |  | $ | 15 |  |  | $ | (14 | ) |  | $ | 6,495 |
|  | Amortized Cost |  |  | Unrealized Gains |  |  | Unrealized Losses |  |  | Fair Value |
As of December 31, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. government securities |  | $ | 14,946 |  |  | $ | 14 |  |  | $ | (15 | ) |  | $ | 14,945 |
Commercial paper |  |  | 8,772 |  |  |  | — |  |  |  | — |  |  |  | 8,772 |
Overnight repurchase agreement |  |  | 9,000 |  |  |  | — |  |  |  | — |  |  |  | 9,000 |
Total short-term investments |  | $ | 32,718 |  |  | $ | 14 |  |  | $ | (15 | ) |  | $ | 32,717 |

X
- Definition Tabular disclosure of information about investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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