Insurance and Contractholder Liabilities - Account Balances including Disposal Groups (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Current
Market risk benefits, current	$ 30	$ 25
Unearned premiums, current, including held for sale liabilities		753
Total, including held for sale liabilities, current		6,480
Current insurance and contractholder liabilities	5,984	5,388
Non-current
Market risk benefits, non-current	800	760
Unearned premiums, non-current, including held for sale liabilities		31
Total, including liabilities held for sale, non-current		10,741
Non-current insurance and contractholder liabilities	10,309	10,254
Total
Market risk benefits	830	785	$ 891
Unearned premiums, including held for sale liabilities		784	836
Total, including held for sale liabilities		17,221	18,510
Total insurance and contractholder liabilities	$ 16,293	15,642	16,429
Held-for-Sale | Medicare Advantage and related Cigna Healthcare businesses
Current
Insurance and contractholder liabilities current, classified as held for sale		(1,092)
Non-current
Insurance and contractholder liabilities, non-current, classified as held for sale		(487)
Total
Insurance and contractholder liabilities classified as held for sale		(1,579)	(2,081)
Unpaid claims classified as liabilities of business held for sale		983	1,378	$ 823
Unearned premiums classified as liabilities of business held for sale		85	161
Contractholder deposit funds classified as liabilities held for sale		103	115
Cigna Healthcare
Current
Unpaid claims and claim expenses, current, including held for sale liabilities		4,932
Future policy benefits, current, including held for sale liabilities		91
Contractholder deposit funds, current, including held for sale liabilities		9
Non-current
Unpaid claims and claim expenses, non-current, including held for sale liabilities		86
Future policy benefits, non-current, including held for sale liabilities		507
Contractholder deposit funds, non-current, including liabilities held for sale		115
Total
Unpaid claims and claim expenses, including held for sale liabilities		5,018	5,863	$ 5,092
Future policy benefits, including held for sale liabilities		598	607
Contractholder deposit funds, including liabilities held for sale		124	141
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	$ 427