Segment Information - Revenue from External Customers (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Revenue from External Customer [Line Items]
Premiums	$ 9,081	$ 11,436	$ 30,973	$ 34,493
Total revenues from external customers	69,515	63,609	201,721	180,776
Pharmacy revenues
Revenue from External Customer [Line Items]
Revenue from contract with customer	56,054	48,284	158,336	135,421
Service
Revenue from External Customer [Line Items]
Revenue from contract with customer	4,380	3,889	12,412	10,862
Service, Fees And Other Revenues [Member]
Revenue from External Customer [Line Items]
Revenue from contract with customer	4,380	3,889	12,412	10,862
Other revenue
Revenue from External Customer [Line Items]
Revenue from contract with customer	276	267	552	509
Evernorth Health Services
Revenue from External Customer [Line Items]
Total revenues from external customers	59,982	51,552	169,470	144,689
Cigna Healthcare
Revenue from External Customer [Line Items]
Total revenues from external customers	9,460	11,919	31,986	35,752
Other Operations
Revenue from External Customer [Line Items]
Total revenues from external customers	68	137	260	333
Operating Segments \| Evernorth Health Services \| Pharmacy revenues
Revenue from External Customer [Line Items]
Revenue from contract with customer	56,441	49,252	160,656	138,612
Operating Segments \| Evernorth Health Services \| Network revenues
Revenue from External Customer [Line Items]
Revenue from contract with customer	32,525	27,353	91,319	76,795
Operating Segments \| Evernorth Health Services \| Home delivery and specialty revenues
Revenue from External Customer [Line Items]
Revenue from contract with customer	20,513	18,909	59,424	53,384
Operating Segments \| Evernorth Health Services \| Other revenues
Revenue from External Customer [Line Items]
Revenue from contract with customer	3,403	2,990	9,913	8,433
Operating Segments \| Evernorth Health Services \| Service, Fees And Other Revenues [Member]
Revenue from External Customer [Line Items]
Revenue from contract with customer	3,921	3,345	11,150	9,635
Operating Segments \| Cigna Healthcare
Revenue from External Customer [Line Items]
Premiums	8,936	11,296	30,556	34,135
Operating Segments \| Cigna Healthcare \| Service, Fees And Other Revenues [Member]
Revenue from External Customer [Line Items]
Revenue from contract with customer	1,881	1,902	5,331	5,223
Operating Segments \| Cigna Healthcare \| U.S. Healthcare
Revenue from External Customer [Line Items]
Premiums	7,889	10,385	27,505	31,448
Operating Segments \| Cigna Healthcare \| U.S. Healthcare \| Employer insured
Revenue from External Customer [Line Items]
Premiums	4,705	4,382	14,077	13,125
Operating Segments \| Cigna Healthcare \| U.S. Healthcare \| Medicare Advantage
Revenue from External Customer [Line Items]
Premiums	0	2,110	2,363	6,604
Operating Segments \| Cigna Healthcare \| U.S. Healthcare \| Stop loss
Revenue from External Customer [Line Items]
Premiums	1,908	1,689	5,655	5,022
Operating Segments \| Cigna Healthcare \| U.S. Healthcare \| Individual and Family Plans
Revenue from External Customer [Line Items]
Premiums	788	1,001	2,588	3,016
Operating Segments \| Cigna Healthcare \| U.S. Healthcare \| Other
Revenue from External Customer [Line Items]
Premiums	488	1,203	2,822	3,681
Operating Segments \| Cigna Healthcare \| International Health
Revenue from External Customer [Line Items]
Premiums	1,047	911	3,051	2,687
Operating Segments \| Other Operations
Revenue from External Customer [Line Items]
Premiums	68	122	227	285
Operating Segments \| Other Operations \| Pharmacy revenues
Revenue from External Customer [Line Items]
Revenue from contract with customer	14	14	41	47
Operating Segments \| Other Operations \| Service, Fees And Other Revenues [Member]
Revenue from External Customer [Line Items]
Revenue from contract with customer	0	19	31	64
Corporate and Eliminations
Revenue from External Customer [Line Items]
Premiums	77	18	190	73
Corporate and Eliminations \| Pharmacy revenues
Revenue from External Customer [Line Items]
Revenue from contract with customer	(401)	(982)	(2,361)	(3,238)
Corporate and Eliminations \| Service, Fees And Other Revenues [Member]
Revenue from External Customer [Line Items]
Revenue from contract with customer	(1,422)	(1,377)	(4,100)	(4,060)
Corporate
Revenue from External Customer [Line Items]
Total revenues from external customers	5	1	5	2
Intersegment Eliminations
Revenue from External Customer [Line Items]
Total revenues from external customers	(1,751)	(2,342)	(6,276)	(7,227)
Intersegment Eliminations \| Evernorth Health Services
Revenue from External Customer [Line Items]
Total revenues from external customers	(380)	(1,045)	(2,336)	(3,558)
Intersegment Eliminations \| Cigna Healthcare
Revenue from External Customer [Line Items]
Total revenues from external customers	(1,357)	(1,279)	(3,901)	(3,606)
Intersegment Eliminations \| Other Operations
Revenue from External Customer [Line Items]
Total revenues from external customers	$ (14)	$ (18)	$ (39)	$ (63)