v3.26.1
Policyholder Account Balances, Future Policy Benefits and Claims - Balances of and Changes in Liability for Future Policy Benefits (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2026
Dec. 31, 2025
Dec. 31, 2024
Liability for Future Policy Benefit, Activity [Line Items]      
Balance $ 9,195 $ 9,309  
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]      
Beginning balance 1,834 1,847  
Beginning balance at original discount rate 1,850 1,905  
Effect of changes in cash flow assumptions   0 $ 31
Effect of actual variances from expected experience   (19) (28)
Adjusted beginning of year balance   1,831 1,908
Issuances 45 210  
Interest accrual 22 92  
Net premiums collected (79) (360)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 1,819 1,850  
Effect of changes in discount rate assumptions (48) (16)  
Ending balance 1,771 1,834  
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]      
Beginning balance 9,427 9,258  
Beginning balance at original discount rate 9,498 9,585  
Effect of changes in cash flow assumptions   0 20
Effect of actual variances from expected experience   (30) (37)
Adjusted beginning of year balance   9,468 9,568
Issuances 45 210  
Interest accrual 117 477  
Benefit payments (179) (757)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 9,451 9,498  
Effect of changes in discount rate assumptions (262) (71)  
Ending balance 9,189 9,427  
Adjustment due to reserve flooring 8 8  
Net liability for future policy benefits 7,426 7,601  
Less: reinsurance recoverable 3,687 3,788  
Net liability for future policy benefits, after reinsurance recoverable 3,739 3,813  
Discounted expected future gross premiums 3,823 3,953  
Expected future gross premiums 5,916 6,014  
Expected future benefit payments 15,116 15,241  
Life Contingent Payout Annuities      
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]      
Beginning balance 0 0  
Beginning balance at original discount rate 0 0  
Effect of changes in cash flow assumptions   0 0
Effect of actual variances from expected experience   0 0
Adjusted beginning of year balance   0 0
Issuances 27 141  
Interest accrual 0 1  
Net premiums collected (27) (142)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 0 0  
Effect of changes in discount rate assumptions 0 0  
Ending balance 0 0  
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]      
Beginning balance 1,273 1,204  
Beginning balance at original discount rate 1,318 1,289  
Effect of changes in cash flow assumptions   0 (2)
Effect of actual variances from expected experience   (5) (5)
Adjusted beginning of year balance   1,313 1,282
Issuances 27 141  
Interest accrual 14 57  
Benefit payments (42) (162)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 1,312 1,318  
Effect of changes in discount rate assumptions (65) (45)  
Ending balance 1,247 1,273  
Adjustment due to reserve flooring 0 0  
Net liability for future policy benefits 1,247 1,273  
Less: reinsurance recoverable 672 703  
Net liability for future policy benefits, after reinsurance recoverable 575 570  
Discounted expected future gross premiums 0 0  
Expected future gross premiums 0 0  
Expected future benefit payments $ 1,901 $ 1,906  
Weighted average interest accretion rate 4.40% 4.40%  
Weighted average discount rate 5.30% 5.00%  
Weighted average duration of liability (in years) 6 years 6 years  
Term and Whole Life Insurance      
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]      
Beginning balance $ 813 $ 737  
Beginning balance at original discount rate 836 774  
Effect of changes in cash flow assumptions   0 58
Effect of actual variances from expected experience   (13) (17)
Adjusted beginning of year balance   823 815
Issuances 15 60  
Interest accrual 10 39  
Net premiums collected (19) (78)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 829 836  
Effect of changes in discount rate assumptions (39) (23)  
Ending balance 790 813  
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]      
Beginning balance 1,378 1,322  
Beginning balance at original discount rate 1,380 1,353  
Effect of changes in cash flow assumptions   0 27
Effect of actual variances from expected experience   (17) (20)
Adjusted beginning of year balance   1,363 1,360
Issuances 15 60  
Interest accrual 18 74  
Benefit payments (20) (114)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 1,376 1,380  
Effect of changes in discount rate assumptions (33) (2)  
Ending balance 1,343 1,378  
Adjustment due to reserve flooring 8 8  
Net liability for future policy benefits 561 573  
Less: reinsurance recoverable 401 408  
Net liability for future policy benefits, after reinsurance recoverable 160 165  
Discounted expected future gross premiums 1,910 1,971  
Expected future gross premiums 3,293 3,334  
Expected future benefit payments $ 2,321 $ 2,328  
Weighted average interest accretion rate 6.00% 6.20%  
Weighted average discount rate 5.60% 5.30%  
Weighted average duration of liability (in years) 7 years 7 years  
Disability Income Insurance      
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]      
Beginning balance $ 33 $ 53  
Beginning balance at original discount rate 37 59  
Effect of changes in cash flow assumptions   0 (19)
Effect of actual variances from expected experience   0 (12)
Adjusted beginning of year balance   37 28
Issuances 3 9  
Interest accrual 0 2  
Net premiums collected 0 (2)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 40 37  
Effect of changes in discount rate assumptions (5) (4)  
Ending balance 35 33  
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]      
Beginning balance 499 545  
Beginning balance at original discount rate 478 535  
Effect of changes in cash flow assumptions   0 (30)
Effect of actual variances from expected experience   (1) (25)
Adjusted beginning of year balance   477 480
Issuances 3 9  
Interest accrual 7 30  
Benefit payments (10) (41)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 477 478  
Effect of changes in discount rate assumptions 11 21  
Ending balance 488 499  
Adjustment due to reserve flooring 0 0  
Net liability for future policy benefits 453 466  
Less: reinsurance recoverable 21 20  
Net liability for future policy benefits, after reinsurance recoverable 432 446  
Discounted expected future gross premiums 785 809  
Expected future gross premiums 1,110 1,126  
Expected future benefit payments $ 785 $ 789  
Weighted average interest accretion rate 6.30% 6.30%  
Weighted average discount rate 5.50% 5.20%  
Weighted average duration of liability (in years) 6 years 6 years  
Long Term Care Insurance      
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]      
Beginning balance $ 988 $ 1,057  
Beginning balance at original discount rate 977 1,072  
Effect of changes in cash flow assumptions   0 (8)
Effect of actual variances from expected experience   (6) 1
Adjusted beginning of year balance   971 1,065
Issuances 0 0  
Interest accrual 12 50  
Net premiums collected (33) (138)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 950 977  
Effect of changes in discount rate assumptions (4) 11  
Ending balance 946 988  
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]      
Beginning balance 6,277 6,187  
Beginning balance at original discount rate 6,322 6,408  
Effect of changes in cash flow assumptions   0 25
Effect of actual variances from expected experience   (7) 13
Adjusted beginning of year balance   6,315 $ 6,446
Issuances 0 0  
Interest accrual 78 316  
Benefit payments (107) (440)  
Derecognition (lapses) 0 0  
Ending balance at original discount rate 6,286 6,322  
Effect of changes in discount rate assumptions (175) (45)  
Ending balance 6,111 6,277  
Adjustment due to reserve flooring 0 0  
Net liability for future policy benefits 5,165 5,289  
Less: reinsurance recoverable 2,593 2,657  
Net liability for future policy benefits, after reinsurance recoverable 2,572 2,632  
Discounted expected future gross premiums 1,128 1,173  
Expected future gross premiums 1,513 1,554  
Expected future benefit payments $ 10,109 $ 10,218  
Weighted average interest accretion rate 5.10% 5.00%  
Weighted average discount rate 5.60% 5.30%  
Weighted average duration of liability (in years) 8 years 8 years