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- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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- Definition

Amount of realized and unrealized gain (loss) on 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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The cash outflow for the purchase of amounts due from customers, clients, lessees, borrowers, or others under the terms of its agreements therewith.

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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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Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Related Party Transaction [Line Items]
Net investment and other gains (losses)	$ (0.2)	$ (4.7)	$ 30.8	$ (21.0)
Included in net income			29.5		$ (0.5)
Loans, at cost	234.9		234.9		144.8
Unfunded Commitments	112.6		112.6		93.4
Accrued underwriting expenses and other liabilities	109.0		109.0		73.9
Equity securities
Related Party Transaction [Line Items]
Included in net income			28.3		$ (0.4)
Related Party
Related Party Transaction [Line Items]
Purchase of loans	207.0		459.7
Net investment and other gains (losses)			27.9
Unfunded Commitments	55.0		55.0
Investment management fees	2.6		7.4
Accrued underwriting expenses and other liabilities	2.6		2.6
Related Party \| Mortgage And Private Loans
Related Party Transaction [Line Items]
Loans, at cost	277.2		277.2
Related Party \| Other Investments
Related Party Transaction [Line Items]
Loans, at cost	$ 138.6		$ 138.6