v3.25.2

Reserve for Losses and Loss Adjustment Expenses - Narrative (Details) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
	Nov. 11, 2024	Jul. 02, 2024	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Reserve For Losses And Loss Adjustment Expenses [Line Items]
Allowance for credit losses on reinsurance recoverables			$ 1,500	$ 744	$ 1,500	$ 744	$ 1,500	$ 1,200	$ 660	$ 660
Development on prior year loss adverse (favorable) reserves			3,027	10,658	2,896	10,260
Reduction in pre-tax income			(7,327)	(20,189)	(23,336)	(53,149)
Excess and Surplus Lines
Reserve For Losses And Loss Adjustment Expenses [Line Items]
Development on prior year loss adverse (favorable) reserves			2,300	10,700	2,300	10,700
Excess and Surplus Lines \| Commercial Auto LPT \| Commercial Auto LPT
Reserve For Losses And Loss Adjustment Expenses [Line Items]
Development on prior year loss adverse (favorable) reserves			(1,414)	1,420	(1,270)	1,897
Cumulative amounts ceded under loss portfolio transfer			458,000		458,000			$ 459,300
Excess and Surplus Lines \| E&S ADC
Reserve For Losses And Loss Adjustment Expenses [Line Items]
Development on prior year loss adverse (favorable) reserves			10,582	$ 0	10,582	0
Reinsure excess amount		$ 716,600
Reinsurance, aggregate coverage limit	$ 1,183,700	467,100
Payments for reinsurance		$ 313,200
Reinsurance, amount remaining			28,800		28,800
Excess and Surplus Lines \| E&S ADC \| State National
Reserve For Losses And Loss Adjustment Expenses [Line Items]
Reinsure percentage		85.00%
Reinsurance, aggregate coverage limit		$ 397,000
Excess and Surplus Lines \| E&S Top Up ADC
Reserve For Losses And Loss Adjustment Expenses [Line Items]
Reinsure percentage	100.00%
Reinsurance, aggregate coverage limit	$ 75,000
Payments for reinsurance	52,800
Reinsurance, amount remaining			75,000		75,000
Reduction in pre-tax income	$ 52,800
Specialty Admitted Insurance
Reserve For Losses And Loss Adjustment Expenses [Line Items]
Development on prior year loss adverse (favorable) reserves			$ 700		$ 579	$ (442)

Cumulative Amounts Ceded Under Loss Portfolio Transfer

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Reinsurance, Aggregate Coverage Limit

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Reinsurance, Aggregate Coverage Limit, Amount Remaining

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Reinsure Excess Amount

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Cash payments made for reinsurance during the current period.

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Amount of valuation allowance for reinsurance recoverables for losses reported to the ceding insurer but not yet paid, and for amounts expected based upon statistical projections and other measures of incurred losses and loss settlement expenses which have not yet been reported to the ceding insurer.

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Percentage of risk undertaken originally by insurer ceded to reinsurer.

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Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

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James River Group Holdings, Ltd. 10-Q