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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 |  |  |
Money Market Funds | Fair Value Measurements, Recurring | Level 1 |  |  |
Fair Value Disclosures (Details) [Line Items] |  |  |
Cash equivalents | $ 42.4 | $ 35.9 | $ 37.4

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