Quarterly report pursuant to Section 13 or 15(d)

Segment Information (Details)

v3.19.1
Segment Information (Details)
$ in Millions
3 Months Ended
Mar. 31, 2019
USD ($)
segment
Mar. 31, 2018
USD ($)
Segment Reporting [Abstract]    
Number of operating segments | segment 2  
Segment Reporting Information [Line Items]    
Total revenues $ 18,444 $ 13,194
Earnings from operations 685 540
Eliminations    
Segment Reporting Information [Line Items]    
Total revenues (2,484) (2,256)
Managed Care    
Segment Reporting Information [Line Items]    
Total revenues 17,722 12,474
Earnings from operations 615 470
Managed Care | Operating Segments    
Segment Reporting Information [Line Items]    
Total revenues 17,687 12,449
Managed Care | Eliminations    
Segment Reporting Information [Line Items]    
Total revenues 35 25
Specialty Services    
Segment Reporting Information [Line Items]    
Total revenues 3,206 2,976
Earnings from operations 70 70
Specialty Services | Operating Segments    
Segment Reporting Information [Line Items]    
Total revenues 757 745
Specialty Services | Eliminations    
Segment Reporting Information [Line Items]    
Total revenues $ 2,449 $ 2,231