v3.26.1
Basis of Presentation and Significant Accounting Policies (Details) - USD ($)
$ in Millions
3 Months Ended
Jun. 30, 2025
Jun. 30, 2026
Dec. 31, 2025
Accounting Policies [Abstract]      
Cash and cash equivalents   $ 668 $ 348
Securities lending transactions, initial collateral percentage value   102.00%  
Premium receivable, allowance for doubtful accounts   $ 187 167
Self-funded receivables, allowance for doubtful accounts   153 145
Other receivables, allowance for doubtful accounts   $ 1,737 $ 1,509
Allowance for double accounts receivable recoveries $ 209    
Release of allowance for doubtful accounts (129)    
Recovery of accounts receivable related to prior year $ 154