Incentive Fee Expense (Income)

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- Definition

Management And Service Fees, Incentive Rate, Percentage Reduction

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- Definition

Management And Services Fees, Incentive Rate, Cumulative Net Profits, Recovery Hurdle, Percentage

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- Definition

Management And Services Fees, Incentive Rate, Excess Profits, Percentage

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Management And Services Fees, Incentive Rate, Net Profits Hurdle, Percentage

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- Definition

Other Commitment, Minimum Investment Commitment

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- Definition

Other Commitment, Minimum Investment Commitment, Percentage Of Net Tangible Assets

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- Definition

Other Commitments, Capital Account Withdrawal, Monthly, Withdrawal, Maximum

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- Definition

Other Commitments, Capital Account Withdrawal, Notice Period

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- Definition

Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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- Definition

Amount of cash and cash equivalent, and cash and cash equivalent restricted to withdrawal or usage; attributable to continuing operation. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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- Definition

Rate based on performance for management and service fees under arrangement to manage operations, including, but not limited to, investment.

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- Definition

Rate for management and service fees under arrangement to manage operations, including, but not limited to, investment.

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- Definition

Amount of expense for investment management fee, including, but not limited to, expense in connection with research, selection, supervision, and custody of investment.

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Amount of cash and cash equivalent restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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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.

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Investments - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
Investments - Narrative (Details) - USD ($) $ in Thousands	May 21, 2026	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Apr. 01, 2026	Dec. 31, 2025	Dec. 31, 2024
Net Investment Income [Line Items]
Management fees		$ 16,432	$ 13,889	$ 46,544	$ 40,574
Restricted cash and cash equivalents		129,300		129,300			$ 109,731
Cash, cash equivalents and restricted cash		1,313,618	1,065,217	1,313,618	1,065,217		1,172,090	$ 1,100,852
Cash and cash equivalents		1,184,318		1,184,318			1,062,359
Capital Requirements \| Asset Pledged as Collateral
Net Investment Income [Line Items]
Investments, fair value		283,200		283,200			263,100
Restricted cash and cash equivalents		5,500		5,500			1,400
Trust Accounts \| Asset Pledged as Collateral
Net Investment Income [Line Items]
Investments, fair value		279,300		279,300			265,000
Restricted cash and cash equivalents		2,200		2,200			2,100
Underwriting Obligations \| Asset Pledged as Collateral
Net Investment Income [Line Items]
Investments, fair value		78,600		78,600			90,400
Restricted cash and cash equivalents		121,600		121,600			106,200
TS Hamilton Fund
Net Investment Income [Line Items]
Management fee percentage	2.50%
Management fees		15,700	13,300	44,300	38,700
Incentive allocation	30.00%
Incentive allocation, reduction (as a percent)	50.00%
Incentive allocation, cumulative net profits (as a percent)	200.00%
Incentive allocation, excess profits (as a percent)	25.00%
Incentive allocation, net profits (as a percent)	10.00%
Incentive allocation expense (income)		146,700	$ 40,200	341,200	$ 221,000
Cash and cash equivalents		$ 528,992		$ 528,992			$ 648,726
TS Hamilton Fund \| Hamilton Re \| Sub-Series A Interests
Net Investment Income [Line Items]
Capital account withdrawal, notice period	55 days
TS Hamilton Fund \| Hamilton Re \| Sub-Series B Interests
Net Investment Income [Line Items]
Capital account withdrawal, notice period	6 months
Maximum monthly withdrawal						8.33%
Two Sigma Hamilton Fund, LLC \| Hamilton Re
Net Investment Income [Line Items]
Commitment for investment in Two Sigma Funds	$ 1,800,000
Investment in Two Sigma Funds, as a percentage of net tangible assets	60.00%