Segment Information - Revenue from External Customers (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue from External Customer [Line Items]
Premiums	$ 41,154	$ 42,627	$ 39,714
Total revenues from external customers	172,529	159,157	152,176
Intersegment Eliminations
Revenue from External Customer [Line Items]
Premiums	(9)	(28)	(13)
Total revenues from external customers	(6,474)	(5,644)	(3,574)
Operating Segments | International businesses to be sold
Revenue from External Customer [Line Items]
Premiums	3,205	3,039	2,884
Operating Segments | Domestic, Disability, Life And Accident
Revenue from External Customer [Line Items]
Premiums	0	4,423	4,225
Operating Segments | Other Operations
Revenue from External Customer [Line Items]
Premiums	221	124	147
Evernorth
Revenue from External Customer [Line Items]
Total revenues from external customers	127,692	112,647	107,354
Evernorth | Intersegment Eliminations
Revenue from External Customer [Line Items]
Total revenues from external customers	(4,203)	(3,655)	(2,380)
Cigna Healthcare
Revenue from External Customer [Line Items]
Total revenues from external customers	41,378	38,826	37,455
Cigna Healthcare | Intersegment Eliminations
Revenue from External Customer [Line Items]
Total revenues from external customers	(2,271)	(1,966)	(1,168)
Other Operations
Revenue from External Customer [Line Items]
Total revenues from external customers	3,459	7,684	7,367
Other Operations | Intersegment Eliminations
Revenue from External Customer [Line Items]
Total revenues from external customers	0	(23)	(26)
Pharmacy revenues
Revenue from External Customer [Line Items]
Revenues	121,413	107,769	103,099
Pharmacy revenues | Intersegment Eliminations
Revenue from External Customer [Line Items]
Revenues	(4,398)	(3,905)	(2,457)
Network revenues | Operating Segments
Revenue from External Customer [Line Items]
Revenues	64,992	56,365	51,430
Home delivery and specialty revenues | Operating Segments
Revenue from External Customer [Line Items]
Revenues	54,391	49,906	49,226
Other | Operating Segments
Revenue from External Customer [Line Items]
Revenues	6,428	5,403	4,900
Cigna Healthcare | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Premiums	37,737	35,069	32,471
Insured | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Premiums	14,315	13,389	12,523
Stop loss | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Premiums	4,868	4,614	4,328
Other | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Premiums	1,290	1,135	1,040
Medicare Advantage | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Premiums	8,362	7,565	6,314
Medicare Part D | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Premiums	1,499	1,593	1,699
Other | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Premiums	4,815	4,301	4,185
International Health | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Premiums	2,588	2,472	2,382
Total fees and other revenues
Revenue from External Customer [Line Items]
Revenues	9,962	8,761	9,363
Total fees and other revenues | Intersegment Eliminations
Revenue from External Customer [Line Items]
Revenues	(2,067)	(1,711)	(1,104)
Fees | Evernorth | Operating Segments
Revenue from External Customer [Line Items]
Revenues	6,070	4,611	4,165
Fees | Cigna Healthcare | Operating Segments
Revenue from External Customer [Line Items]
Revenues	5,743	5,491	6,022
Fees | Other Operations | Operating Segments
Revenue from External Customer [Line Items]
Revenues	19	116	123
Other revenues | Operating Segments
Revenue from External Customer [Line Items]
Revenues	$ 197	$ 254	$ 157