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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The carrying amount as of the balance sheet date due the entity from (a) agents and insureds, (b) uncollected premiums and (c) others, net of the allowance for doubtful accounts.

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

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Amount of allowance for credit loss on reinsurance recoverable.

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Reinsurance - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Reinsurance - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Premiums receivable	$ 7,280,682	$ 5,139,471
Premium receivable, allowance for credit loss	3,514	4,606	$ 2,776
Reinsurance Recoverables, Including Reinsurance Premium Paid	5,300,000	4,700,000
Reinsurance recoverable, allowance for credit loss	$ 13,279	$ 12,169	$ 8,344
Reinsurance Recoverable \| Reinsurer Concentration Risk \| Customer One
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	17.60%	20.80%
Reinsurance Recoverable \| Reinsurer Concentration Risk \| Customer Two
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	14.30%	7.00%
Reinsurance Recoverable \| Reinsurer Concentration Risk \| Customer Three
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	8.70%	5.40%
Allowance for Reinsurance Recoverable \| Customer Concentration Risk \| Customer One
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	10.90%	14.30%
Allowance for Reinsurance Recoverable \| Customer Concentration Risk \| Customer Two
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	10.70%	9.10%
Allowance for Reinsurance Recoverable \| Customer Concentration Risk \| Customer Three
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	8.10%	8.00%
Ceded Credit Risk, Secured \| Reinsurance Recoverable \| Reinsurer Concentration Risk
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	60.60%	47.20%
Rated A- or higher \| Ceded Credit Risk, Unsecured \| Reinsurance Recoverable \| Reinsurer Concentration Risk
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	38.50%	52.00%
Rated lower than A- \| Ceded Credit Risk, Unsecured \| Reinsurance Recoverable \| Reinsurer Concentration Risk
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Concentration risk percentage	0.90%	0.80%