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Investment Securities (Restrictions on Redemption Frequency and Advance Notice Requirements) (Details) - Hedge funds $ in Millions | Dec. 31, 2016 USD ($) fund
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Investment securities |
Number of Investments Held | fund | 5
Trading Securities, Other | $ 59.8
Distributions from inactive hedge funds | 1.0
Outstanding redemptions | 2.4
30-59 days notice |
Investment securities |
Trading Securities, Other | 37.5
60-89 days notice |
Investment securities |
Trading Securities, Other | 19.9
90-119 days notice |
Investment securities |
Trading Securities, Other | 2.4
Monthly |
Investment securities |
Trading Securities, Other | 0.0
Monthly | 30-59 days notice |
Investment securities |
Trading Securities, Other | 0.0
Monthly | 60-89 days notice |
Investment securities |
Trading Securities, Other | 0.0
Monthly | 90-119 days notice |
Investment securities |
Trading Securities, Other | 0.0
Quarterly |
Investment securities |
Trading Securities, Other | 15.9
Quarterly | 30-59 days notice |
Investment securities |
Trading Securities, Other | 15.9
Quarterly | 60-89 days notice |
Investment securities |
Trading Securities, Other | 0.0
Quarterly | 90-119 days notice |
Investment securities |
Trading Securities, Other | 0.0
Semi-annual |
Investment securities |
Trading Securities, Other | 41.5
Semi-annual | 30-59 days notice |
Investment securities |
Trading Securities, Other | 21.6
Semi-annual | 60-89 days notice |
Investment securities |
Trading Securities, Other | 19.9
Semi-annual | 90-119 days notice |
Investment securities |
Trading Securities, Other | $ 0.0
Lock-up period expiring 2018 |
Investment securities |
Number of Investments Held | fund | 1
Trading Securities, Other | $ 21.5
Annual |
Investment securities |
Trading Securities, Other | 2.4
Annual | 30-59 days notice |
Investment securities |
Trading Securities, Other | 0.0
Annual | 60-89 days notice |
Investment securities |
Trading Securities, Other | 0.0
Annual | 90-119 days notice |
Investment securities |
Trading Securities, Other | $ 2.4

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