Insurance and Contractholder Liabilities - Account Balances (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current
Market risk benefits, current	$ 25	$ 37
Unearned premiums, current, including held for sale liabilities	753	846
Total, current	6,480	6,633
Current insurance and contractholder liabilities	5,388	5,514
Non-current
Market risk benefits, non-current	760	966
Unearned premiums, non-current, including held for sale liabilities	31	22
Total, non-current	10,741	11,421
Non-current insurance and contractholder liabilities	10,254	10,904
Total
Market risk benefits	785	1,003
Unearned premiums, including held for sale liabilities	784	868
Total	17,221	18,054
Total insurance and contractholder liabilities	15,642	16,418
Held-for-Sale | Medicare Advantage and related Cigna Healthcare businesses
Current
Insurance and contractholder liabilities current, classified as held for sale	(1,092)	(1,119)
Non-current
Insurance and contractholder liabilities, non-current, classified as held for sale	(487)	(517)
Total
Insurance and contractholder liabilities classified as held for sale	(1,579)	(1,636)
Unpaid claims classified as liabilities of business held for sale	983	823
Unearned premiums classified as liabilities of business held for sale	85	261
Contractholder deposit funds classified as liabilities held for sale	103	123
Cigna Healthcare
Current
Unpaid claims and claim expenses, current, including held for sale liabilities	4,932	5,017
Future policy benefits, current, including held for sale liabilities	91	97
Contractholder deposit funds, current, including held for sale liabilities	9	12
Non-current
Unpaid claims and claim expenses, non-current, including held for sale liabilities	86	75
Future policy benefits, non-current, including held for sale liabilities	507	518
Contractholder deposit funds, non-current, including liabilities held for sale	115	133
Total
Unpaid claims and claim expenses			$ 4,176	$ 4,261
Unpaid claims and claim expenses, including held for sale liabilities	5,018	5,092
Future policy benefits, including held for sale liabilities	598	615
Contractholder deposit funds, including liabilities held for sale	124	145
Cigna Healthcare | Held-for-Sale | Medicare Advantage and related Cigna Healthcare businesses
Total
Future policy benefits classified as liabilities of business held for sale	408	429
Other Operations
Current
Unpaid claims and claim expenses, current	147	99
Future policy benefits, current	157	163
Contractholder deposit funds, current	366	362
Non-current
Unpaid claims and claim expenses, non-current	144	154
Future policy benefits, non-current	3,140	3,375
Contractholder deposit funds, non-current	5,958	6,178
Total
Unpaid claims and claim expenses	291	253
Total liability for future policy benefits	3,297	3,538
Contractholder deposit funds	$ 6,324	$ 6,540	$ 6,700