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Investment Securities - Fair Value of Hedge Funds Subject to Restrictions on Redemption Frequency (Details) $ in Millions | Dec. 31, 2022 USD ($) fund | Dec. 31, 2021 USD ($)
--- | --- | ---
Total private equity funds and hedge funds included in other long-term investments |  |
Investment securities |  |
Other long-term investments largest single investment | $ 49.0 | $ 31.3
Trading security, fair value | 197.8 | 153.8
Fair value unfunded commitments | $ 94.3 | 44.0
Private equity funds |  |
Investment securities |  |
Number of investments | fund | 16 |
Trading security, fair value | $ 140.6 | 141.8
Fair value unfunded commitments | 94.3 | 44.0
Private equity funds | Aerospace/Defense/Government |  |
Investment securities |  |
Trading security, fair value | 59.4 | 69.8
Fair value unfunded commitments | 37.5 | 11.8
Private equity funds | Financial services |  |
Investment securities |  |
Trading security, fair value | 77.1 | 67.7
Fair value unfunded commitments | 54.3 | 29.3
Private equity funds | Real estate |  |
Investment securities |  |
Trading security, fair value | 4.1 | 4.3
Fair value unfunded commitments | $ 2.5 | 2.9
Hedge funds |  |
Investment securities |  |
Number of investments | fund | 2 |
Trading security, fair value | $ 57.2 | 12.0
Fair value unfunded commitments | 0.0 | 0.0
Hedge funds | Long/short equity financials and business services |  |
Investment securities |  |
Trading security, fair value | 49.0 | 0.0
Fair value unfunded commitments | 0.0 | 0.0
Hedge funds | European small/mid cap |  |
Investment securities |  |
Trading security, fair value | 8.2 | 12.0
Fair value unfunded commitments | $ 0.0 | $ 0.0

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