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Investments - Equity Securities without Readily Determinable Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
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.

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- Definition

Equity Securities without Readily Determinable Fair Value, Initial Cost

+ References

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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

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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

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