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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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Rate of interest on investment.

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The cash inflow associated with the sale and maturity (principal being due) of other investments, prepayment and call (request of early payment) of other investments not otherwise defined in the taxonomy.

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The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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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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Investments - Schedule of Private Debt and Equity (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025 USD ($) note	Jun. 30, 2024 USD ($) project	Jun. 30, 2025 USD ($) note	Jun. 30, 2024 USD ($)	Apr. 11, 2025 note	Dec. 31, 2024 USD ($)
Net Investment Income [Line Items]
Carrying Value	$ 58,140		$ 58,140			$ 36,700
Investment Income	986	$ 1,909	1,186	$ 1,764
Renewable Energy Llcs
Net Investment Income [Line Items]
Carrying Value	7,322		7,322			7,690
Investment Income	(320)	$ 1,241	(320)	955
Number of underlying projects sold \| project		2
Proceeds from sale of equity method investments		$ 1,200
Renewable energy notes receivable
Net Investment Income [Line Items]
Carrying Value	0		0			0
Investment Income	0	0	0	138
Limited partnerships
Net Investment Income [Line Items]
Carrying Value	17,742		17,742			15,108
Investment Income	851	517	860	402
Private debt
Net Investment Income [Line Items]
Carrying Value	33,076		33,076			13,902
Investment Income	455	151	646	269
Excess and Surplus Lines
Net Investment Income [Line Items]
Carrying Value	57,676		57,676			36,236
Investment Income	986	1,616	1,186	1,394
Excess and Surplus Lines \| Renewable Energy Llcs
Net Investment Income [Line Items]
Carrying Value	7,322		7,322			7,690
Investment Income	$ (320)	948	(320)	662
Proceeds from sale of equity method investments		880
Excess and Surplus Lines \| Renewable Energy Llcs \| Investment in LLC
Net Investment Income [Line Items]
Cash distributions from LLCs			$ 48	161
Excess and Surplus Lines \| Renewable Energy Llcs \| Minimum \| Investment in LLC \| Various LLCs
Net Investment Income [Line Items]
Ownership percentage	3.60%		3.60%
Excess and Surplus Lines \| Renewable Energy Llcs \| Maximum \| Investment in LLC \| Various LLCs
Net Investment Income [Line Items]
Ownership percentage	5.00%		5.00%
Excess and Surplus Lines \| Renewable energy notes receivable
Net Investment Income [Line Items]
Carrying Value	$ 0		$ 0			0
Investment Income	$ 0	0	$ 0	61
Number of notes issued \| note	2		2
Rate of interest	12.00%		12.00%
Total principal balance received				608
Excess and Surplus Lines \| Limited partnerships
Net Investment Income [Line Items]
Carrying Value	$ 17,278		$ 17,278			14,644
Investment Income	851	517	860	402
Outstanding commitments to invest	9,300		9,300
Excess and Surplus Lines \| Private debt
Net Investment Income [Line Items]
Carrying Value	33,076		33,076			13,902
Investment Income	$ 455	151	$ 646	269
Excess and Surplus Lines \| Private speciality credit
Net Investment Income [Line Items]
Number of notes issued \| note	7		7
Commitment to investment in notes	$ 5,600		$ 5,600
Excess and Surplus Lines \| Private speciality credit \| Sixth Street
Net Investment Income [Line Items]
Commitment to investment in notes	$ 64,600		$ 64,600
Number of notes maturing \| note					3
Excess and Surplus Lines \| Private speciality credit \| Notes receivable one
Net Investment Income [Line Items]
Rate of interest	4.25%		4.25%
Excess and Surplus Lines \| Private speciality credit \| Notes receivable one \| Sixth Street
Net Investment Income [Line Items]
Rate of interest					6.79%
Excess and Surplus Lines \| Private speciality credit \| Notes receivable two
Net Investment Income [Line Items]
Rate of interest	5.25%		5.25%
Excess and Surplus Lines \| Private speciality credit \| Notes receivable two \| Sixth Street
Net Investment Income [Line Items]
Rate of interest					8.04%
Excess and Surplus Lines \| Private speciality credit \| Notes receivable three
Net Investment Income [Line Items]
Rate of interest	6.50%		6.50%
Excess and Surplus Lines \| Private speciality credit \| Notes receivable three \| Sixth Street
Net Investment Income [Line Items]
Rate of interest					9.04%
Excess and Surplus Lines \| Private speciality credit \| Notes receivable four
Net Investment Income [Line Items]
Rate of interest	8.00%		8.00%
Corporate and Other
Net Investment Income [Line Items]
Carrying Value	$ 464		$ 464			464
Investment Income	0	293	0	370
Corporate and Other \| Renewable Energy Llcs
Net Investment Income [Line Items]
Carrying Value	0		0			0
Investment Income	0	293	0	293
Proceeds from sale of equity method investments		293
Corporate and Other \| Renewable energy notes receivable
Net Investment Income [Line Items]
Carrying Value	0		0			0
Investment Income	$ 0	0	$ 0	77
Number of notes issued \| note	2		2
Rate of interest	12.00%		12.00%
Total principal balance received				761
Corporate and Other \| Limited partnerships
Net Investment Income [Line Items]
Carrying Value	$ 464		$ 464			464
Investment Income	0	0	0	0
Corporate and Other \| Private debt
Net Investment Income [Line Items]
Carrying Value	0		0			$ 0
Investment Income	$ 0	$ 0	$ 0	$ 0