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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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- Definition 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 -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI https://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(2)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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