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Investment Securities - Hedge Funds and Private Equity Funds (Details) $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($) fund	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Investments in trading securities | $	$ 30.9	$ 0.0
Private equity funds
Debt and Equity Securities, FV-NI [Line Items]
Number of investments | fund	17
Hedge funds
Debt and Equity Securities, FV-NI [Line Items]
Number of investments | fund	2
Total private equity funds and hedge funds included in other long-term investments
Debt and Equity Securities, FV-NI [Line Items]
Largest single fund investment | $	$ 49.9		$ 49.0

X

- Definition

Amount of increase (decrease) of investment in debt and equity securities, measured at fair value with changes in fair value recognized in net income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 19
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3444-108585

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- Definition

Number of Investments

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- Definition

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

+ References

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