v3.25.2
Reportable Segments - Schedule of Reportable Segments Financial Performance (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Segment Reporting Information        
Net investment income $ 754 $ 712 $ 1,608 $ 1,476
Net gains (losses) on investments and derivatives (144) (103) (493) (267)
Pension and other postretirement remeasurement gains (losses) 0 9 (78) 11
Amortization of purchased intangibles (57) (70) (116) (139)
Gain (loss) on disposition 890 0 890 0
Less: Net (loss) income attributable to noncontrolling interest (10) 16 (9) (4)
Net income applicable to common shareholders, basic 2,079 301 2,645 1,490
Net income applicable to common shareholders, diluted 2,079 301 2,645 1,490
Operating segments        
Segment Reporting Information        
Amortization of purchased intangibles (57) (70) (116) (139)
Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment        
Segment Reporting Information        
Adjusted net income (loss) by segment, after-tax 819 453 1,038 720
Net gains (losses) on investments and derivatives (144) (103) (493) (267)
Pension and other postretirement remeasurement gains (losses) 0 9 (78) 11
Amortization of purchased intangibles (11) (19) (24) (37)
Gain (loss) on disposition 893 1 893 5
Income tax (expense) benefit on Property-Liability and reconciling items (606) (78) (730) (337)
Property-Liability        
Segment Reporting Information        
Less: Net (loss) income attributable to noncontrolling interest (10) 16 (9) (4)
Property-Liability | Operating segments        
Segment Reporting Information        
Underwriting income (loss) by segment 1,280 (145) 1,640 753
Net investment income 687 643 1,470 1,345
Net gains (losses) on investments and derivatives (190) (103) (519) (265)
Amortization of purchased intangibles (46) (51) (92) (102)
Property-Liability | Operating segments | Allstate Protection        
Segment Reporting Information        
Underwriting income (loss) by segment 1,283 (142) 1,647 761
Property-Liability | Operating segments | Run-off Property-Liability        
Segment Reporting Information        
Underwriting income (loss) by segment (3) (3) (7) (8)
Property-Liability | Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment        
Segment Reporting Information        
Net investment income 687 643 1,470 1,345
Protection Services | Operating segments        
Segment Reporting Information        
Adjusted net income (loss) by segment, after-tax 60 55 115 109
Net investment income 25 23 49 44
Net gains (losses) on investments and derivatives 1 (1) (9) (6)
Amortization of purchased intangibles (9) (13) (18) (24)
Allstate Health and Benefits | Operating segments        
Segment Reporting Information        
Adjusted net income (loss) by segment, after-tax 4 58 34 114
Net investment income 5 25 30 48
Net gains (losses) on investments and derivatives (1) 0 (2) 2
Amortization of purchased intangibles (2) (6) (6) (13)
Corporate and Other | Operating segments        
Segment Reporting Information        
Adjusted net income (loss) by segment, after-tax (94) (104) (191) (210)
Net investment income 37 21 59 39
Net gains (losses) on investments and derivatives $ 46 $ 1 $ 37 $ 2