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Investment Securities - Investments In Private Equity Funds Subject to Lock-Up Periods (Details) - Private equity funds $ in Millions	Jun. 30, 2023 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Fair Value	$ 229.7
1 – 3 years
Debt and Equity Securities, FV-NI [Line Items]
Fair Value	4.3
3 – 5 years
Debt and Equity Securities, FV-NI [Line Items]
Fair Value	73.4
5 – 10 years
Debt and Equity Securities, FV-NI [Line Items]
Fair Value	141.9
Greater than 10 years
Debt and Equity Securities, FV-NI [Line Items]
Fair Value	$ 10.1

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