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MARKETABLE SECURITIES - Fair Value Measurement (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | $ 320.3 | $ 341.2
Level 1 |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 173.1 | 190.6
Level 1 | Mutual Funds and Equities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 163.1 | 176.9
Level 1 | Money Market Funds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 10.0 | 13.7
Level 2 |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 147.2 | 150.6
Level 2 | U.S. Government Issued Debt Securities (Agency and Treasury) |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 92.0 | 90.1
Level 2 | Corporate Debt Securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 32.5 | 34.0
Level 2 | Asset-Backed Debt Securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 7.8 | 5.6
Level 2 | Municipal Bonds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 6.8 | 9.8
Level 2 | Other Fixed Income Securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | $ 8.1 | $ 11.1

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