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Investment Securities (Fair Value of Hedge Funds Subject to Restrictions on Redemption Frequency) (Details) $ in Millions | Dec. 31, 2017 USD ($) fund | Dec. 31, 2016 USD ($)
--- | --- | ---
Long/short equity REIT |  |
Investment securities |  |
Carrying value | $ 20.8 |
Hedge funds |  |
Investment securities |  |
Number of investments held | fund | 1 |
Private equity funds |  |
Investment securities |  |
Number of investments held | fund | 10 |
Carrying value | $ 70.4 |
Total hedge and private equity funds included in other long-term investments |  |
Investment securities |  |
Other long-term investments largest single investment | 54.9 | $ 21.5
Carrying value | 125.3 | 82.6
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | $ 99.3 | 123.6
Hedge funds | Long/short banks and financial |  |
Investment securities |  |
Number of investments held | fund | 1 |
Carrying value | $ 54.9 | 21.5
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 0.0 | 0.0
Hedge funds | Long/short equity REIT |  |
Investment securities |  |
Carrying value | 0.0 | 19.9
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 0.0 | 0.0
Hedge funds | Hedge funds |  |
Investment securities |  |
Carrying value | 54.9 | 41.4
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 0.0 | 0.0
Private equity funds | Private equity funds |  |
Investment securities |  |
Carrying value | 70.4 | 41.2
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 99.3 | 123.6
Private equity funds | Manufacturing/Industrial |  |
Investment securities |  |
Carrying value | 43.3 | 19.4
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 10.4 | 22.9
Private equity funds | Aerospace/Defense/Government |  |
Investment securities |  |
Carrying value | 15.8 | 19.4
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 12.9 | 25.9
Private equity funds | Direct lending |  |
Investment securities |  |
Carrying value | 7.1 | 1.4
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 23.1 | 28.6
Private equity funds | Financial Services |  |
Investment securities |  |
Carrying value | 4.2 | 1.0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | 11.7 | 5.0
Private equity funds | Insurance |  |
Investment securities |  |
Carrying value | 0.0 | 0.0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments | $ 41.2 | $ 41.2
Lock-up period expiring 2018 | Hedge funds |  |
Investment securities |  |
Number of investments held | fund | 1 |
Carrying value | $ 54.9 |

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