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Financial Instruments - Fair value hierarchy (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021
Reverse repurchase agreements | Government Securities and Obligations | Minimum |  |
Financial Instruments |  |
Percentage of investment amount to collateralized deposits value | 102.00% |
Recurring |  |
Assets: |  |
Total | $ 85,666 | $ 40,853
Recurring | Level 1 |  |
Assets: |  |
Total | 10,144 | 1,853
Recurring | Level 2 |  |
Assets: |  |
Total | 75,522 | 39,000
Recurring | Money market funds |  |
Assets: |  |
Cash equivalents | 8,145 | 1,853
Recurring | Money market funds | Level 1 |  |
Assets: |  |
Cash equivalents | 8,145 | 1,853
Recurring | Corporate debt securities |  |
Assets: |  |
Cash equivalents | 4,396 |
Short-term investments | 17,121 |
Recurring | Corporate debt securities | Level 2 |  |
Assets: |  |
Cash equivalents | 4,396 |
Short-term investments | 17,121 |
Recurring | Commercial paper |  |
Assets: |  |
Cash equivalents | 3,996 |
Short-term investments | 5,980 |
Recurring | Commercial paper | Level 2 |  |
Assets: |  |
Cash equivalents | 3,996 |
Short-term investments | 5,980 |
Recurring | Yankee securities |  |
Assets: |  |
Short-term investments | 4,029 |
Recurring | Yankee securities | Level 2 |  |
Assets: |  |
Short-term investments | 4,029 |
Recurring | Treasury Bills |  |
Assets: |  |
Short-term investments | 1,999 |
Recurring | Treasury Bills | Level 1 |  |
Assets: |  |
Short-term investments | 1,999 |
Recurring | Reverse repurchase agreements |  |
Assets: |  |
Cash equivalents | 3,000 |
Short-term investments | 37,000 | 39,000
Recurring | Reverse repurchase agreements | Level 2 |  |
Assets: |  |
Cash equivalents | 3,000 |
Short-term investments | $ 37,000 | $ 39,000

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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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