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Investments - Equity Securities without Readily Determinable Fair Value (Details) - USD ($) $ in Millions | Mar. 31, 2026 | Dec. 31, 2025
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Investments, Debt and Equity Securities [Abstract] |  |
Initial cost | $ 84.7 | $ 82.5
Cumulative upward adjustments | 55.7 | 55.6
Cumulative downward adjustments (including impairments) | (22.8) | (22.8)
Carrying value | $ 117.6 | $ 115.3

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- Definition Equity Securities without Readily Determinable Fair Value, Downward Price Adjustment And Impairment Loss, Cumulative Amount + References No definition available. + Details
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- Definition Amount of investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479536/321-10-50-3 + Details
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- Definition Amount of cumulative gain from upward price adjustment on investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479536/321-10-50-3 + Details
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