Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Marketable Securities [Line Items]
Net unrealized gain (loss)	$ 0.2	$ 2.6	$ 1.6	$ 3.9
Proceeds from maturity of AFS securities	300.0	0.0	725.2	101.7
Debt securities, net unrealized gain (loss)	(0.2)	0.0	0.6	0.0
Purchases of available-for-sale securities	99.8	$ 75.0	413.9	$ 175.0
Variable Interest Entity, Primary Beneficiary
Marketable Securities [Line Items]
Fair value of deconsolidated investment in affiliate, equity securities	$ 12.1		$ 12.1		$ 15.8

Equity Securities, Fair Value, Consolidation

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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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-14

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
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+ References

No definition available.

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Amount of cash outflow to acquire investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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