v3.25.2
Loss and Loss Adjustment Expense Reserves (Tables)
6 Months Ended
Jun. 30, 2025
Insurance [Abstract]  
Summary of loss and LAE reserve activity
The following table summarizes the loss and loss adjustment expense (“LAE”) reserve activity of the Ark/WM Outrigger segment for the three and six months ended June 30, 2025 and 2024:

Three Months Ended June 30,Six Months Ended June 30,
Millions2025202420252024
Gross beginning balance$2,253.9 $1,744.5 $2,127.5 $1,605.1 
Less: beginning reinsurance recoverable on unpaid
   losses
(480.6)(404.5)(434.4)(340.8)
Net loss and LAE reserves1,773.3 1,340.0 1,693.1 1,264.3 
Loss and LAE incurred relating to:
Current year losses181.1 182.6 467.4 362.9 
Prior year losses(17.1)(6.9)(69.9)(7.2)
Net incurred loss and LAE164.0 175.7 397.5 355.7 
Loss and LAE paid relating to:
Current year losses(29.5)(4.3)(112.7)(8.3)
Prior year losses(104.0)(78.8)(179.8)(175.5)
Net paid loss and LAE(133.5)(83.1)(292.5)(183.8)
Foreign currency translation and other adjustments
   to loss and LAE reserves
16.2 (1.0)21.9 (4.6)
Net ending balance1,820.0 1,431.6 1,820.0 1,431.6 
Plus: ending reinsurance recoverable on unpaid
   losses
468.5 458.5 468.5 458.5 
Gross ending balance$2,288.5 $1,890.1 $2,288.5 $1,890.1