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Investment Securities (Restrictions on Redemption Frequency and Advance Notice Requirements) (Details) - Hedge funds $ in Millions	Sep. 30, 2018 USD ($) fund
Debt and Equity Securities, FV-NI [Line Items]
Number of investments | fund	1
September 2018
Debt and Equity Securities, FV-NI [Line Items]
Number of hedge funds	1
Other long-term investments | $	$ 59.6

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- Definition

Cost of investments in equity securities and other forms of securities that provide ownership interests classified as trading.

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Number of Investments

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Number of investments held.

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