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Transfer Of Legacy Business On Acquisition

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

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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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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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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		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Jan. 01, 2024	Jun. 30, 2022	Dec. 31, 2021	Jul. 01, 2021	Jun. 30, 2021	Jan. 01, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Premiums ceded	$ 1,136,909	$ 1,131,486	$ 3,488,632	$ 2,907,002
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses	6,356,456	5,358,852	6,356,456	5,358,852		$ 5,938,511	$ 5,880,735		$ 4,314,515		$ 4,500,802
Reinsurance balances payable	1,669,592		1,669,592				1,583,253
Forecast
Related Party Transaction [Line Items]
Put/call option, proportion of initial shares					33.30%
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	236,500	$ 316,200	661,100	$ 316,200
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses	1,100,000		1,100,000				902,800
Reinsurance balances payable	408,000		408,000				$ 258,400
Senior notes, face amount	$ 35,000		$ 35,000
Senior notes, stated percentage	6.50%		6.50%