v3.26.3
Investments - Credit Quality Indicators (Details) - Commercial Portfolio Segment
$ in Millions
Sep. 30, 2026
USD ($)
Dec. 31, 2025
USD ($)
Greater than 2.0    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 7.3 $ 6.8
Financing receivable, originated year one 6.8 4.5
Financing receivable, originated year two 8.4 0.5
Financing receivable, originated year three 0.0 12.9
Financing receivable, originated year four 12.8 8.6
Prior 29.8 35.2
Total $ 65.1 $ 68.5
% of Total 0.207 0.207
1.5 to 2.0    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 19.6 $ 13.2
Financing receivable, originated year one 13.3 19.5
Financing receivable, originated year two 12.5 13.7
Financing receivable, originated year three 9.2 9.2
Financing receivable, originated year four 6.1 19.3
Prior 14.8 9.1
Total $ 75.5 $ 84.0
% of Total 0.240 0.253
1.0 to 1.5    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 17.6 $ 32.7
Financing receivable, originated year one 31.4 27.8
Financing receivable, originated year two 22.2 15.5
Financing receivable, originated year three 10.7 11.1
Financing receivable, originated year four 12.7 23.3
Prior 26.8 2.6
Total $ 121.4 $ 113.0
% of Total 0.386 0.341
Less than 1.0    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 0.3 $ 0.0
Financing receivable, originated year one 0.0 2.7
Financing receivable, originated year two 6.2 14.9
Financing receivable, originated year three 10.1 25.4
Financing receivable, originated year four 19.4 19.7
Prior 16.5 3.2
Total $ 52.5 $ 65.9
% of Total 0.167 0.199
Total    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 44.8 $ 52.7
Financing receivable, originated year one 51.5 54.5
Financing receivable, originated year two 49.3 44.6
Financing receivable, originated year three 30.0 58.6
Financing receivable, originated year four 51.0 70.9
Prior 87.9 50.1
Total $ 314.5 $ 331.4
% of Total 1.000 1.000
70% and less    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 37.1 $ 50.4
Financing receivable, originated year one 47.4 48.5
Financing receivable, originated year two 36.6 27.4
Financing receivable, originated year three 17.9 25.7
Financing receivable, originated year four 18.0 32.2
Prior 41.5 44.4
Total $ 198.5 $ 228.6
% of Total 0.631 0.690
71% to 80%    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 4.7 $ 0.0
Financing receivable, originated year one 1.8 5.0
Financing receivable, originated year two 11.7 11.0
Financing receivable, originated year three 8.3 7.5
Financing receivable, originated year four 18.1 16.0
Prior 26.3 5.7
Total $ 70.9 $ 45.2
% of Total 0.225 0.136
81% to 95%    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 0.0 $ 2.3
Financing receivable, originated year one 2.3 1.0
Financing receivable, originated year two 1.0 2.4
Financing receivable, originated year three 0.0 10.5
Financing receivable, originated year four 3.8 12.0
Prior 13.9 0.0
Total $ 21.0 $ 28.2
% of Total 0.067 0.085
Greater than 95%    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 3.0 $ 0.0
Financing receivable, originated year one 0.0 0.0
Financing receivable, originated year two 0.0 3.8
Financing receivable, originated year three 3.8 14.9
Financing receivable, originated year four 11.1 10.7
Prior 6.2 0.0
Total $ 24.1 $ 29.4
% of Total 0.077 0.089
Total    
Financing Receivable, Credit Quality Indicator [Line Items]    
Financing receivable, originated current year $ 44.8 $ 52.7
Financing receivable, originated year one 51.5 54.5
Financing receivable, originated year two 49.3 44.6
Financing receivable, originated year three 30.0 58.6
Financing receivable, originated year four 51.0 70.9
Prior 87.9 50.1
Total $ 314.5 $ 331.4
% of Total 1.000 1.000