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The maximum amount of statutory capital that may be paid out as dividends without prior approval from a regulatory agency.

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The maximum percentage of statutory capital and surplus that may be paid out as dividends without prior approval from a regulatory agency.

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Unencumbered Assets which are not held in trust for the benefit of cedants.

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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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Percentage of voting equity interest acquired in business combination.

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Amount, after tax, of pro forma income (loss) of combined entity as if acquisition date of business combination occurred as of beginning of period.

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Amount of pro forma revenue of combined entity as if acquisition date of business combination occurred as of beginning of period.

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Amount of expense for acquisition-related cost incurred to effect business combination. Includes, but is not limited to, finder's fee; advisory, legal, accounting, valuation, and other professional and consulting fees; and general administrative cost, including cost of maintaining internal acquisition department.

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Amount of acquiree's earnings (loss) since acquisition date of business combination included in consolidated statement of income.

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Amount of acquiree's revenue since acquisition date of business combination included in consolidated statement of income.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount of dividends that can be declared or paid without approval of regulatory agency.

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Assured Life Re Acquisition - Additional Information (Details) - USD ($) $ in Millions		3 Months Ended		5 Months Ended	6 Months Ended		12 Months Ended
	Jan. 21, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026
Assured Guaranty Re Ltd. \| BERMUDA
Business Combination [Line Items]
Dividend payment restrictions schedule, percentage of statutory capital and surplus					25.00%
Statutory amount available for dividend payments without regulatory approval		$ 41.0		$ 41.0	$ 41.0		$ 41.0
Unencumbered asset		27.0		27.0	27.0		27.0
Dividend payment restrictions schedule amount of statutory capital					31.0
Assured Life Re Acquisition
Business Combination [Line Items]
Voting equity interest acquired, percentage	100.00%
Cash purchase price	$ 158.0
Acquiree's revenue since acquisition date, actual		11.0		25.0
Acquiree's earnings (loss) since acquisition date, actual		(1.0)		$ 1.0
Business Combination, Acquisition-Related Cost, Expense					4.0		$ 7.0
Pro forma revenue		194.0	$ 268.0		451.0	$ 617.0
Pro forma income (loss), after tax		$ 40.0	$ 90.0		$ 121.0	$ 268.0
Assured Life Re Acquisition \| Pension Risk Transfers Insurance Liabilities
Business Combination [Line Items]
Acquired assets, weighted average useful life	10 years 3 months 18 days
Assured Life Re Acquisition \| Multi-year Guaranteed Annuity Policyholder Balances
Business Combination [Line Items]
Acquired assets, weighted average useful life	2 years 3 months 18 days
Assured Life Re Acquisition, Pension Risk Transfers
Business Combination [Line Items]
Value of business acquired	$ 14.0
Assured Life Re Acquisition, Multi-year Guaranteed Annuities
Business Combination [Line Items]
Value of business acquired	$ (14.0)