v3.25.1
Reserves for Losses and Loss Adjustment Expenses (Tables)
 3 Months Ended
Mar. 31, 2025
Insurance [Abstract]  
Schedule of Reserves for Losses and Loss Adjustment Expenses
The following table provides a reconciliation of reserves for losses and loss adjustment expenses (“LAE”):
For the Three Months Ended
March 31,
(in millions)20252024
Net reserves - beginning of the year$3,003.9 $2,747.1 
Add:
Losses and LAE incurred during current calendar year, net of reinsurance:
Current accident year147.1 195.2 
Prior accident years1.0 24.8 
Losses and LAE incurred during calendar year, net of reinsurance148.1 220.0 
Deduct:
Losses and LAE payments made during current calendar year, net of reinsurance:
Current accident year38.6 6.7 
Prior accident years144.6 174.8 
Losses and LAE payments made during current calendar year, net of reinsurance:183.2 181.5 
Add/(Deduct):
Foreign exchange adjustments— (1.3)
Net reserves - end of period2,968.8 2,784.3 
Add:
Reinsurance recoverables on unpaid losses and LAE, end of period2,711.4 2,758.8 
Gross reserves - end of period$5,680.2 $5,543.1 
Schedule of Impact from (Favorable) Unfavorable Development of Prior Accident Years’ Loss and LAE Reserves on Each Reporting Segment
The impact from the unfavorable (favorable) development of prior accident years’ loss and LAE reserves on each reporting segment is presented below: 
For the Three Months Ended
March 31,
(in millions)20252024
Casualty Lines$0.8 $0.7 
Specialty Lines0.1 0.7 
Run-off Lines0.1 23.4 
Total unfavorable (favorable) prior-year development$1.0 $24.8