Liability for Unpaid Losses and Loss Adjustment Expense - Reconciliation (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Reinsurance Recoverables on Unpaid Losses	$ 674,746	$ 482,315	$ 477,870
Short-duration Insurance Contracts, Liability for Unpaid Claims and Claims Adjustment Expense, Accumulated Unallocated Claim Adjustment Expense	16,811	13,486
Unpaid losses and loss adjustment expenses	1,089,966	760,357	$ 661,203	$ 482,232
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	398,409	264,556
Property and Casualty, Personal Insurance Product Line
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Reinsurance Recoverables on Unpaid Losses	674,746	482,315
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	$ 398,409	$ 264,556

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Undiscounted amount, after reinsurance, of the liability for unpaid claims and allocated claim adjustment expense for short-duration insurance contracts. Excludes unallocated claim adjustment expense.

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Amount of liability for unallocated claim adjustment expense for short-duration insurance 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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