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v3.23.1

Investments in Marketable Securities - Debt Securities, Available-for-Sale (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Available-for-sale |  |
Cost | $ 252.9 | $ 252.3
Unrealized losses | (0.8) | (1.3)
Fair value | 252.1 | 251.0
Trading |  |
Cost | 20.6 | 19.7
Unrealized losses | (1.5) | (1.7)
Fair value | $ 19.1 | $ 18.0

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