v3.25.2

Reserves for Losses and Loss Adjustment Expenses - Schedule of Reserves for Losses and Loss Adjustment Expenses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Net reserves - beginning of the year			$ 3,003.9	$ 2,747.1
Losses and LAE incurred during current calendar year, net of reinsurance:
Current accident year			301.6	381.1
Prior accident years			2.6	65.6
Losses and LAE incurred during calendar year, net of reinsurance	$ 156.1	$ 226.7	304.2	446.7
Losses and LAE payments made during current calendar year, net of reinsurance:
Current accident year			55.2	23.2
Prior accident years			286.9	406.3
Losses and LAE payments made during current calendar year, net of reinsurance:			342.1	429.5
Add/(Deduct):
Foreign exchange adjustments			1.2	(2.2)
Net reserves - end of period	2,967.2	2,762.1	2,967.2	2,762.1
Reinsurance recoverables on unpaid losses and LAE, end of period	2,642.2	2,754.8	2,642.2	2,754.8
Gross reserves - end of period	$ 5,609.4	$ 5,516.9	$ 5,609.4	$ 5,516.9	$ 5,798.6

Additional Changes For Reserves For Losses and Loss Adjustment Expense

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The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

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Amount, after effects of reinsurance, of payments to settle claims incurred in the current period and related claims settlement costs.

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Amount of foreign currency gain (loss) which decreases (increases) the cost of settling unpaid claims after deduction of reinsurance recoveries. Includes, but is not limited to, claims which have been incurred but not reported.

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Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred and costs incurred in the claim settlement process.

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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

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Argo Group International Holdings, Inc. 10-Q