v3.26.1
Segments - Reconciliation of Gross Margin to Consolidated Income (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Revenue:    
Premium revenue $ 10,172 $ 10,628
Service revenue 22 22
Revenue from external customers 10,194 10,650
Other operating revenues 602 497
Total revenue 10,796 11,147
Operating expenses:    
Medical care costs 9,270 9,479
Cost of service revenue 21 19
Segment expenses 9,291 9,498
Other operating expenses 1,422 1,216
Operating income 83 433
Less: interest expense 54 43
Income before income tax expense 29 390
Medical margin    
Operating expenses:    
Segment margin 902 1,149
Service margin    
Operating expenses:    
Segment margin 1 3
Operating segments | Medicaid    
Revenue:    
Premium revenue 7,927 8,130
Service revenue 0 0
Revenue from external customers 7,927 8,130
Operating expenses:    
Medical care costs 7,296 7,339
Cost of service revenue 0 0
Segment expenses 7,296 7,339
Operating segments | Medicaid | Medical margin    
Operating expenses:    
Segment margin 631 791
Operating segments | Medicaid | Service margin    
Operating expenses:    
Segment margin 0 0
Operating segments | Medicare    
Revenue:    
Premium revenue 1,517 1,468
Service revenue 0 0
Revenue from external customers 1,517 1,468
Operating expenses:    
Medical care costs 1,363 1,296
Cost of service revenue 0 0
Segment expenses 1,363 1,296
Operating segments | Medicare | Medical margin    
Operating expenses:    
Segment margin 154 172
Operating segments | Medicare | Service margin    
Operating expenses:    
Segment margin 0 0
Operating segments | Marketplace    
Revenue:    
Premium revenue 724 1,004
Service revenue 0 0
Revenue from external customers 724 1,004
Operating expenses:    
Medical care costs 608 821
Cost of service revenue 0 0
Segment expenses 608 821
Operating segments | Marketplace | Medical margin    
Operating expenses:    
Segment margin 116 183
Operating segments | Marketplace | Service margin    
Operating expenses:    
Segment margin 0 0
Operating segments | Other    
Revenue:    
Premium revenue 4 26
Service revenue 22 22
Revenue from external customers 26 48
Operating expenses:    
Medical care costs 3 23
Cost of service revenue 21 19
Segment expenses 24 42
Operating segments | Other | Medical margin    
Operating expenses:    
Segment margin 1 3
Operating segments | Other | Service margin    
Operating expenses:    
Segment margin $ 1 $ 3