v3.26.1
Stockholders' Equity (Schedule of Accumulated Other Comprehensive Income (Loss) by Component) (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Total stockholder's equity at beginning of period $ 11,621  
OCI, before Reclassifications, Net of Tax, Attributable to Parent (263) $ 196
Amounts reclassified from accumulated other comprehensive income (loss) net of tax (12) (10)
Other comprehensive income (loss) after tax (expense) benefit (251) 206
Total stockholder's equity at end of period 10,857 10,279
Reclassification from AOCI, tax 3 1
Tax (expense) benefit on other comprehensive income (loss) 60 (42)
Accumulated other comprehensive income (loss)    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Total stockholder's equity at beginning of period (1,098) (1,991)
Total stockholder's equity at end of period (1,349) (1,785)
Net unrealized gains (losses) on investments | Investments    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Total stockholder's equity at beginning of period (15) (13)
OCI, before Reclassifications, Net of Tax, Attributable to Parent (12) (5)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax (5) (2)
Other comprehensive income (loss) after tax (expense) benefit (7) (3)
Total stockholder's equity at end of period (22) (16)
Reclassification from AOCI, tax 1 0
Tax (expense) benefit on other comprehensive income (loss) 2 1
Net unrealized gains (losses) on investments | Net unrealized gains and losses on other investments    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Total stockholder's equity at beginning of period (988) (1,876)
OCI, before Reclassifications, Net of Tax, Attributable to Parent (431) 277
Amounts reclassified from accumulated other comprehensive income (loss) net of tax (6) (6)
Other comprehensive income (loss) after tax (expense) benefit (425) 283
Total stockholder's equity at end of period (1,413) (1,593)
Reclassification from AOCI, tax 2 1
Tax (expense) benefit on other comprehensive income (loss) 115 (74)
Pension and postretirement benefits    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Total stockholder's equity at beginning of period (166) (191)
OCI, before Reclassifications, Net of Tax, Attributable to Parent 0 0
Amounts reclassified from accumulated other comprehensive income (loss) net of tax (1) (2)
Other comprehensive income (loss) after tax (expense) benefit 1 2
Total stockholder's equity at end of period (165) (189)
Reclassification from AOCI, tax 0 0
Tax (expense) benefit on other comprehensive income (loss) 0 0
Cumulative impact of changes in discount rates used to measure long duration contracts    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Total stockholder's equity at beginning of period 192 353
OCI, before Reclassifications, Net of Tax, Attributable to Parent 214 (114)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax 0 0
Other comprehensive income (loss) after tax (expense) benefit 214 (114)
Total stockholder's equity at end of period 406 239
Reclassification from AOCI, tax 0 0
Tax (expense) benefit on other comprehensive income (loss) (57) 31
Cumulative foreign currency translation adjustment    
AOCI Attributable to Parent, Net of Tax [Roll Forward]    
Total stockholder's equity at beginning of period (121) (264)
OCI, before Reclassifications, Net of Tax, Attributable to Parent (34) 38
Amounts reclassified from accumulated other comprehensive income (loss) net of tax 0 0
Other comprehensive income (loss) after tax (expense) benefit (34) 38
Total stockholder's equity at end of period (155) (226)
Reclassification from AOCI, tax 0 0
Tax (expense) benefit on other comprehensive income (loss) $ 0 $ 0