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Investment Securities (Fair Value of Hedge Funds Subject to Restrictions on Redemption Frequency) (Details) $ in Millions | Dec. 31, 2019 USD ($) fund | Dec. 31, 2018 USD ($)
--- | --- | ---
Private equity funds |  |
Investment securities |  |
Number of Investments Held | fund | 12 |
Trading security, fair value | $ 106.5 |
Hedge funds |  |
Investment securities |  |
Number of Investments Held | fund | 1 |
Total private equity funds and hedge funds included in other long-term investments |  |
Investment securities |  |
Other long-term investments largest single investment | $ 54.6 | $ 54.3
Trading security, fair value | 161.1 | 146.1
Fair value unfunded commitments | 50.2 | 76.7
Private equity funds | Private equity funds |  |
Investment securities |  |
Trading security, fair value | 106.5 | 91.8
Fair value unfunded commitments | 50.2 | 76.7
Private equity funds | Manufacturing/Industrial |  |
Investment securities |  |
Trading security, fair value | 57.7 | 42.9
Fair value unfunded commitments | 4.1 | 10.5
Private equity funds | Aerospace/Defense/Government |  |
Investment securities |  |
Trading security, fair value | 33.8 | 27.6
Fair value unfunded commitments | 23.3 | 34.9
Private equity funds | Financial services |  |
Investment securities |  |
Trading security, fair value | 15.0 | 8.3
Fair value unfunded commitments | 22.8 | 13.6
Private equity funds | Direct lending |  |
Investment securities |  |
Trading security, fair value | 0.0 | 13.0
Fair value unfunded commitments | 0.0 | 17.7
Hedge funds | Hedge funds |  |
Investment securities |  |
Trading security, fair value | 54.6 | 54.3
Fair value unfunded commitments | 0.0 | 0.0
Hedge funds | Hedge Fund, Long/ Short Equity Banks and Financial |  |
Investment securities |  |
Trading security, fair value | 54.6 | 54.3
Fair value unfunded commitments | $ 0.0 | $ 0.0

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