v3.21.2

Reinsurance - Narrative (Details) - USD ($)	Jul. 31, 2019	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019	Dec. 27, 2018
Reinsurance Retention Policy [Line Items]
Reinsurance recoverable for unpaid claims and claims adjustments		$ 565,549,000	$ 592,571,000
Reinsurance recoverable for unpaid claims and claims adjustments, valuation allowance		0	0
Reinsurance retention policy, excess retention, amount reinsured	$ 2,178,535,000
Reinsurance retention policy, amount retained	600,000,000
Reinsurance recoverable for paid and unpaid claims and claims adjustments, adverse development cover	155,000,000
Reinsurance recoverable for paid and unpaid claims and claims adjustments, ceded cumulative losses	445,000,000
Reinsurance recoverables, including reinsurance premium paid		565,549,000	592,571,000	$ 617,496,000	$ 623,422,000
Deferred gain on retroactive reinsurance		54,254,000	74,941,000
Collateral by third party	445,000,000	430,552,000
Maximum
Reinsurance Retention Policy [Line Items]
Reinsurance recoverables on paid losses, gross	312,786,000
Diversified Reinsurance
Reinsurance Retention Policy [Line Items]
Assets and liabilities associated with reinsurance business retroceded						100.00%
Diversified Reinsurance | Miscellaneous
Reinsurance Retention Policy [Line Items]
Reinsurance recoverable for unpaid claims and claims adjustments		62,541,000	67,972,000
AmTrust Reinsurance
Reinsurance Retention Policy [Line Items]
Reinsurance recoverable for unpaid claims and claims adjustments	$ 445,000,000
Reinsurance recoverables, including reinsurance premium paid		$ 499,254,000	$ 519,941,000

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Reinsurance, Assets And Liabilities, Retroceded, Percentage

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Reinsurance Recoverable For Paid And Unpaid Claims And Claims Adjustments, Ceded Cumulative Losses

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Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

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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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