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Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions | 2 Months Ended | 12 Months Ended
--- | --- | ---
Feb. 15, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Investments in and Advances to Affiliates [Line Items] |  |  |
Equity securities, FV-NI |  | $ 447.9 | $ 64.5
Unrealized gains |  | 59.9 | 8.1
Debt securities, available-for-sale, maturity, year one |  | 100.7 |
Debt securities, available-for-sale, maturity, year two |  | 150.3 |
EQT AB (“EQT”) |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Equity securities, FV-NI |  | 405.1 |
Equity securities, realized gain |  | 43.8 |
Unrealized gains |  | 57.9 |
EQT AB (“EQT”) | Subsequent Event |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Equity interests issued, value | $ 196.0 |  |
Affiliate Sponsored Investment |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Equity securities, FV-NI |  | 23.5 | 28.9
Debt securities, fair value, consolidation |  | $ 18.0 | $ 14.0

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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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