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MARKETABLE SECURITIES - Fair Value Measurement (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
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Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | $ 375.6 | $ 473.6
Level 1 |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 215.5 | 285.5
Level 1 | Mutual Funds and Equities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 190.1 | 254.2
Level 1 | Money Market Funds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 25.4 | 31.3
Level 2 |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 160.1 | 188.1
Level 2 | U.S. Government Issued Debt Securities (Agency and Treasury) |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 82.3 | 81.3
Level 2 | Corporate Debt Securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 46.1 | 65.3
Level 2 | Asset-Backed Debt Securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 8.6 | 12.6
Level 2 | Municipal Bonds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | 12.7 | 12.3
Level 2 | Other Fixed Income Securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total Marketable Securities | $ 10.4 | $ 16.6

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