Segment Information (Financial Data By Reportable Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Reportable segments operating revenues	$ 155,660	$ 136,943	$ 120,808
Operating gain (loss)	8,452	7,489	6,360
Depreciation and amortization of property and equipment	784	668	638
Commercial and Specialty Business Segment [Member]
Segment Reporting Information [Line Items]
Reportable segments operating revenues	41,674	38,809	36,699
Operating gain (loss)	2,933	2,753	2,681
Depreciation and amortization of property and equipment	0	0	0
Government Business Segment [Member]
Segment Reporting Information [Line Items]
Reportable segments operating revenues	96,810	82,919	71,572
Operating gain (loss)	3,297	3,061	2,444
Depreciation and amortization of property and equipment	0	0	0
CarelonRx Segment [Member]
Segment Reporting Information [Line Items]
Operating gain (loss)	1,868	1,684	1,361
CarelonRx Segment [Member] | Unaffiliated [Member]
Segment Reporting Information [Line Items]
Reportable segments operating revenues	14,974	12,655	10,384
CarelonRx Segment [Member] | Affiliated [Member]
Segment Reporting Information [Line Items]
Reportable segments operating revenues	13,552	12,776	11,527
Other [Member]
Segment Reporting Information [Line Items]
Reportable segments operating revenues	13,294	10,250	6,057
Operating gain (loss)	354	(9)	(126)
Depreciation and amortization of property and equipment	784	668	638
Other [Member] | Unaffiliated [Member]
Segment Reporting Information [Line Items]
Reportable segments operating revenues	2,202	2,560	2,153
Other [Member] | Affiliated [Member]
Segment Reporting Information [Line Items]
Reportable segments operating revenues	11,092	7,690	3,904
Segment Eliminations [Member]
Segment Reporting Information [Line Items]
Reportable segments operating revenues	$ (24,644)	$ (20,466)	$ (15,431)