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Investments - Narrative (Details) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2024 USD ($) shares | Sep. 30, 2024 USD ($) shares | Aug. 23, 2024 $ / shares shares | Jan. 05, 2024 $ / shares shares | Dec. 31, 2023 USD ($) | Oct. 06, 2023 $ / shares shares | Oct. 04, 2023 tranche shares
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |  |  |
Technology investments | $ 149.9 | $ 149.9 |  |  | $ 128.0 |  |
Long-term Investments |  |  |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |  |  |
Technology investments | 144.9 | 144.9 |  |  | 124.6 |  |
Short-Term Investments |  |  |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |  |  |
Technology investments | $ 5.0 | $ 5.0 |  |  | $ 3.4 |  |
VOXX International Corporation |  |  |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |  |  |
Shares of investment held (in shares) | shares | 6,463,808 | 6,463,808 |  |  |  |  |
Gain (loss) relating to mark to market adjustment in investment income | $ 14.9 | $ (9.0) |  |  |  |  |
VOXX International Corporation |  |  |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |  |  |
Number of tranches | tranche |  |  |  |  |  |  | 2
VOXX International Corporation | Common Class A |  |  |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |  |  |
Number of shares acquired (in shares) | shares |  |  | 3,152,500 | 1,568,750 |  | 1,568,750 | 3,137,500
Shares purchased, price per share (in dollars per share) | $ / shares |  |  | $ 5 | $ 10 |  | $ 10 |

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