Business Optimization Initiatives (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Business Optimization Initiatives [Line Items]
Business optimization initiatives, incurred cost	$ 39	$ 202	$ 653
Business Optimization, Incurred Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Selling, general and administrative expense	Selling, general and administrative expense	Selling, general and administrative expense
Employee Termination [Member]
Business Optimization Initiatives [Line Items]
Business optimization initiatives, incurred cost			$ 197
Releases	$ (2)
Property and Equipment Impairment and Abandonment [Member]
Business Optimization Initiatives [Line Items]
Business optimization initiatives, incurred cost	7	$ 66	198
Operating Lease Impairment and Abandonment [Member]
Business Optimization Initiatives [Line Items]
Business optimization initiatives, incurred cost	34	136	258
Commercial and Specialty Business [Member]
Business Optimization Initiatives [Line Items]
Business optimization initiatives, incurred cost	20	108	311
Commercial and Specialty Business [Member] | Employee Termination [Member]
Business Optimization Initiatives [Line Items]
Releases	0
CarelonRx Segment [Member]
Business Optimization Initiatives [Line Items]
Business optimization initiatives, incurred cost	0	1	4
CarelonRx Segment [Member] | Employee Termination [Member]
Business Optimization Initiatives [Line Items]
Releases	0
Other Segment [Member]
Business Optimization Initiatives [Line Items]
Business optimization initiatives, incurred cost	3	33	133
Other Segment [Member] | Employee Termination [Member]
Business Optimization Initiatives [Line Items]
Releases	(2)
Government Business [Member]
Business Optimization Initiatives [Line Items]
Business optimization initiatives, incurred cost	16	$ 60	$ 205
Government Business [Member] | Employee Termination [Member]
Business Optimization Initiatives [Line Items]
Releases	$ 0