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Financial Instruments - Fair value hierarchy (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Financial Instruments Measurements |  |  |
Transfers between fair value measurement levels | $ 0 | $ 0 |
Reverse repurchase agreements | Government Securities and Obligations |  |  |
Financial Instruments Measurements |  |  |
Percentage of investment amount to collateralized deposits value | 102.00% |  |
Recurring |  |  |
Assets: |  |  |
Total | $ 322,597 |  | $ 78,709
Recurring | Level 1 |  |  |
Assets: |  |  |
Total | 242,597 |  | 7,709
Recurring | Level 2 |  |  |
Assets: |  |  |
Total | 80,000 |  | 71,000
Recurring | Money market funds |  |  |
Assets: |  |  |
Cash and cash equivalents: | 104,705 |  | 7,709
Recurring | Money market funds | Level 1 |  |  |
Assets: |  |  |
Cash and cash equivalents: | 104,705 |  | 7,709
Recurring | Treasury bills |  |  |
Assets: |  |  |
Cash and cash equivalents: | 19,997 |  |
Short-term investments: | 103,251 |  |
Recurring | Treasury bills | Level 1 |  |  |
Assets: |  |  |
Cash and cash equivalents: | 19,997 |  |
Short-term investments: | 103,251 |  |
Recurring | Treasury notes |  |  |
Assets: |  |  |
Short-term investments: | 14,644 |  |
Recurring | Treasury notes | Level 1 |  |  |
Assets: |  |  |
Short-term investments: | 14,644 |  |
Recurring | Reverse repurchase agreements |  |  |
Assets: |  |  |
Short-term investments: | 80,000 |  | 71,000
Recurring | Reverse repurchase agreements | Level 2 |  |  |
Assets: |  |  |
Short-term investments: | $ 80,000 |  | $ 71,000

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-3 + Details
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