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Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Investments in and Advances to Affiliates [Line Items]
Equity securities, FV-NI	$ 186.5	$ 447.9
Net unrealized gain (loss)	1.4
Debt securities, available-for-sale, maturity, year one	100.4
Debt securities, available-for-sale, maturity, year two	151.7
Proceeds from maturity of AFS securities	101.7
Debt securities, net unrealized gain (loss)	(0.1)
EQT AB (“EQT”)
Investments in and Advances to Affiliates [Line Items]
Equity securities, FV-NI	141.5	405.1
Affiliate Sponsored Investment
Investments in and Advances to Affiliates [Line Items]
Equity securities, FV-NI	$ 21.4	$ 23.5

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Debt Securities, Available-For-Sale, Maturity, Year One

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Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of cash inflow from maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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