Condensed Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues:
Premiums	$ 19,978	$ 18,556	$ 40,102	$ 36,918
Services	491	450	957	874
Investment income	176	77	254	226
Total revenues	20,645	19,083	41,313	38,018
Operating expenses:
Benefits	17,149	14,175	34,445	29,804
Operating costs	2,116	2,354	4,123	4,471
Depreciation and amortization	144	119	286	234
Total operating expenses	19,409	16,648	38,854	34,509
Income from operations	1,236	2,435	2,459	3,509
Interest expense	79	76	147	136
Other expense (income), net	419	(227)	534	70
Income before income taxes and equity in net earnings	738	2,586	1,778	3,303
Provision for income taxes	183	783	416	1,035
Equity in net earnings	33	25	54	33
Net income	$ 588	$ 1,828	$ 1,416	$ 2,301
Basic earnings per common share (in dollars per share)	$ 4.57	$ 13.83	$ 11.00	$ 17.41
Diluted earnings per common share (in dollars per share)	$ 4.55	$ 13.75	$ 10.94	$ 17.31
Services revenue, type	us-gaap:HealthCareMember	us-gaap:HealthCareMember	us-gaap:HealthCareMember	us-gaap:HealthCareMember