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- Definition

Transfer Of Legacy Business On Acquisition

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- Definition

Amount of written premiums ceded to other entities.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

The carrying amount as of the balance sheet date of the known and estimated amounts owed to insurers under reinsurance treaties or other arrangements.

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Amount, after valuation allowance, recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, policy benefits and policy reserves. Excludes premiums paid under reinsurance contracts.

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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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Transactions With Related Parties (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2022	Dec. 31, 2021	Jul. 01, 2021	Mar. 31, 2021	Jan. 01, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Premiums ceded	$ 1,185,088	$ 886,767	$ 2,351,723	$ 1,775,516
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses	5,938,511	$ 4,314,515	5,938,511	$ 4,314,515	$ 5,941,000	$ 5,880,735		$ 4,041,076		$ 4,500,802
Reinsurance balances payable	1,634,700		1,634,700			$ 1,583,253
Greysbridge Holdings Ltd
Related Party Transaction [Line Items]
Percentage ownership							40.00%
Kelso And Company \| Greysbridge Holdings Ltd
Related Party Transaction [Line Items]
Percentage ownership							30.00%
Warburg Pincus LLC \| Greysbridge Holdings Ltd
Related Party Transaction [Line Items]
Percentage ownership							30.00%
Operating affiliates \| Premia Holdings Ltd
Related Party Transaction [Line Items]
Legacy business, amount of liabilities transferred									$ 380,000
Operating affiliates \| Somers Holdings Ltd
Related Party Transaction [Line Items]
Premiums ceded			424,600
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses	964,700		964,700
Reinsurance balances payable	358,400		358,400
Senior notes, face amount	$ 35,000		$ 35,000
Senior notes, stated percentage	6.50%		6.50%
Operating affiliates \| Somers Holdings Ltd \| Non-cumulative preferred shares
Related Party Transaction [Line Items]
Percentage ownership	6.60%		6.60%