Quarterly report pursuant to Section 13 or 15(d)

Health Net (Narrative) (Details)

v3.5.0.2
Health Net (Narrative) (Details)
$ / shares in Units, $ in Millions
 3 Months Ended 6 Months Ended 9 Months Ended
Mar. 24, 2016
USD ($)
$ / shares
shares
Sep. 30, 2016
USD ($)
Sep. 30, 2016
USD ($)
Sep. 30, 2016
USD ($)
Business Acquisition [Line Items]        
Centene's stock price (in dollars per share) | $ / shares $ 62.7      
Health Net, Inc.        
Business Acquisition [Line Items]        
Business combination, consideration transferred, including assumed debt $ 5,990.0      
Assumption of outstanding debt 703.0      
Consideration transferred 5,287.0      
Common stock issued for acquisition 3,038.0      
Payments to acquire business 2,247.0      
Fair value adjustment to stock based compensation $ 2.0      
Share exchange, per share 0.622      
Cash paid with each share (in dollars per share) | $ / shares $ 28.25      
Common stock issued for acquisitions (in shares) | shares 48,449,444      
Goodwill increase     $ 275.0  
Revenue of acquiree since acquisition date, actual   $ 3,981.0   $ 8,604.0
Health Net, Inc. | General and Administrative Expense        
Business Acquisition [Line Items]        
Acquisition related costs   $ 10.0   $ 224.0