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Investment Securities (Investments In Private Equity Funds Subject to Lock-Up Periods) (Details) - Private equity funds $ in Millions | Jun. 30, 2017 USD ($)
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Schedule of Trading Securities and Other Trading Assets [Line Items] |
Other long-term investments | $ 76.4
1-3 years |
Schedule of Trading Securities and Other Trading Assets [Line Items] |
Other long-term investments | 3.6
3-5 years |
Schedule of Trading Securities and Other Trading Assets [Line Items] |
Other long-term investments | 20.9
5-10 years |
Schedule of Trading Securities and Other Trading Assets [Line Items] |
Other long-term investments | 29.7
Greater than 10 years |
Schedule of Trading Securities and Other Trading Assets [Line Items] |
Other long-term investments | $ 22.2

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