Condensed Financial Information of Registrant - Condensed Statements of Operations (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Expenses:
Selling, general and administrative expenses	$ 10,166	$ 9,867	$ 6,533
Legal settlement	1,250	0	0
Other income (expense):
Investment and other income	819	480	443
Gain on divestiture	88	104	0
Debt extinguishment costs	(125)	(61)	(30)
Interest expense	(665)	(728)	(412)
Income tax benefit	477	979	473
Net earnings	1,336	1,794	1,309
Loss attributable to noncontrolling interests	11	14	12
Net earnings attributable to Centene Corporation	$ 1,347	$ 1,808	$ 1,321
Net earnings per share:
Basic earnings per common share (in usd per share)	$ 2.31	$ 3.17	$ 3.19
Diluted earnings per common share (in usd per share)	$ 2.28	$ 3.12	$ 3.14
Parent Company
Expenses:
Selling, general and administrative expenses	$ 9	$ 13	$ 11
Contingent consideration	0	(1)	(24)
Legal settlement	1,116	0	0
Other income (expense):
Investment and other income	38	5	11
Gain on divestiture	118	104	0
Debt extinguishment costs	(125)	(61)	(30)
Interest expense	(641)	(723)	(394)
Loss before income taxes	(1,735)	(687)	(400)
Income tax benefit	(308)	(331)	(172)
Net (loss) before equity in subsidiaries	(1,427)	(356)	(228)
Equity in earnings from subsidiaries	2,763	2,150	1,537
Net earnings	1,336	1,794	1,309
Loss attributable to noncontrolling interests	11	14	12
Net earnings attributable to Centene Corporation	$ 1,347	$ 1,808	$ 1,321
Net earnings per share:
Basic earnings per common share (in usd per share)	$ 2.31	$ 3.17	$ 3.19
Diluted earnings per common share (in usd per share)	$ 2.28	$ 3.12	$ 3.14