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Investment Securities - Hedge Funds and Private Equity Funds (Details) $ in Millions	Mar. 31, 2021 USD ($) fund	Dec. 31, 2020 USD ($)
Private equity funds
Debt and Equity Securities, FV-NI [Line Items]
Number of investments	13
Hedge and private equity funds included in other long-term investments
Debt and Equity Securities, FV-NI [Line Items]
Largest single fund investment | $	$ 23.5	$ 29.1
Hedge funds
Debt and Equity Securities, FV-NI [Line Items]
Number of investments	1

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Number of Investments

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- Definition

The largest investment which the entity has made in a single fund.

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