Fair Value Measurements - Additional Information - Narrative (Details)	12 Months Ended
Dec. 31, 2025 USD ($) quotesPerInvestment	Dec. 31, 2024 USD ($) quotesPerInvestment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Quotes per fixed income investment \| quotesPerInvestment	2.8	3.0
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Privately-held Investments, at fair value	$ 121,800,000
Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Privately-held Investments, at fair value	121,800,000
Total, Privately-held Investments	172,300,000
Assets \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers Into Level 3	0
Settlements and sales	$ (256,000,000.0)
Equity Securities \| Assets \| Recurring \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers out of Level 3		$ 0
Transfers Into Level 3		0
Settlements and sales		$ (7,100,000)

Fair value inputs offered quotes per fixed income investment.

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- Definition

Privately-held Investments trading, at fair value

+ References

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- Definition

Total, Privately-held Investments, including available for sale and trading

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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-Topic 820
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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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