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Investment Securities (Restrictions on Redemption Frequency and Advance Notice Requirements) (Details) - Hedge funds - USD ($) $ in Millions | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Hedge funds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Fair Value | $ 0.0 | $ 54.6
Hedge Fund, Long/ Short Equity Banks and Financial |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Fair Value | $ 0.0 | $ 54.6

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- Details
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- Details
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