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Investment Securities (Investments In Private Equity Funds Subject to Lock-Up Periods) (Details) - Private equity funds $ in Millions | Dec. 31, 2017 USD ($)
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Investment securities |
Carrying value | $ 70.4
1 – 3 years |
Investment securities |
Carrying value | 4.7
3 – 5 years |
Investment securities |
Carrying value | 5.6
5 – 10 years |
Investment securities |
Carrying value | 32.9
10 years |
Investment securities |
Carrying value | $ 27.2

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