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Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Investments in and Advances to Affiliates [Line Items]
Equity securities, FV-NI	$ 37.9	$ 447.9
Unrealized gains on equity securities	2.9	35.5
Proceeds from maturity of AFS securities	511.1	0.0
Debt securities net unrealized (loss) gain	0.8	(2.2)
Variable Interest Entity, Primary Beneficiary
Investments in and Advances to Affiliates [Line Items]
Equity securities, FV-NI	$ 15.8	23.5
EQT AB (“EQT”)
Investments in and Advances to Affiliates [Line Items]
Equity securities, FV-NI		$ 405.1

X

- Definition

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

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.7-03(a)(1)(b))
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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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
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-SubTopic 220
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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
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-11

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