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Fair Value Disclosures (Details) - USD ($) $ in Millions |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2022 | Mar. 31, 2024 | Dec. 31, 2023
Fair Value Disclosures (Details) [Line Items] |  |  |
Fair value hierarchy |  |  |
Debt outstanding |  |  |
Marketable securities |  |  |
Level 1 | Fair Value Measurements, Recurring | Money Market Funds |  |  |
Fair Value Disclosures (Details) [Line Items] |  |  |
Cash equivalents | $ 42.4 | $ 35.9 | $ 37.4

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (aa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
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