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Investment Securities - Fair Value of Hedge Funds Subject to Restrictions on Redemption Frequency (Details) $ in Millions | Dec. 31, 2021 USD ($) fund | Dec. 31, 2020 USD ($)
--- | --- | ---
Total private equity funds and hedge funds included in other long-term investments |  |
Investment securities |  |
Other long-term investments largest single investment | $ 31.3 | $ 29.1
Trading security, fair value | 153.8 | 121.2
Fair value unfunded commitments | $ 44.0 | 45.7
Private equity funds |  |
Investment securities |  |
Number of investments | fund | 12 |
Trading security, fair value | $ 141.8 | 121.2
Fair value unfunded commitments | 44.0 | 45.7
Private equity funds | Aerospace/Defense/Government |  |
Investment securities |  |
Trading security, fair value | 69.8 | 69.1
Fair value unfunded commitments | 11.8 | 15.3
Private equity funds | Financial services |  |
Investment securities |  |
Trading security, fair value | 67.7 | 23.5
Fair value unfunded commitments | 29.3 | 30.4
Private equity funds | Real Estate |  |
Investment securities |  |
Trading security, fair value | 4.3 | 0.0
Fair value unfunded commitments | 2.9 | 0.0
Private equity funds | Manufacturing/Industrial |  |
Investment securities |  |
Trading security, fair value | 0.0 | 28.6
Fair value unfunded commitments | $ 0.0 | 0.0
Hedge funds |  |
Investment securities |  |
Number of investments | fund | 1 |
Trading security, fair value | $ 12.0 | 0.0
Fair value unfunded commitments | 0.0 | 0.0
Hedge funds | European small/mid cap |  |
Investment securities |  |
Trading security, fair value | 12.0 | 0.0
Fair value unfunded commitments | $ 0.0 | $ 0.0

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