Acquisitions (Details) - USD ($) $ in Millions				3 Months Ended	6 Months Ended	12 Months Ended
		Jan. 31, 2023	Jul. 01, 2022	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisitions [Line Items]
Goodwill					$ 16,287	$ 16,287	$ 15,213	$ 15,400
Other intangible assets					5,441	5,441	5,455
Value of business acquired					3,596	3,596	236	263	$ 306
Repurchase agreements					1,419	1,419	1,406
Accrued investment income					941	941	821
Insurance and reinsurance balances receivable					11,933	11,933	11,322
Reinsurance recoverable on losses and loss expenses	[1]				18,901	18,901	17,366
Reinsurance recoverable on policy benefits	[1]				303	303	213
Other assets					12,736	12,736	11,792
Total assets					199,144	199,144	200,054
Unpaid losses and loss expenses					76,323	76,323	72,943	67,811	$ 62,690
Unearned premiums					20,360	20,360	19,101
Future policy benefits					10,120	10,120	5,947
Insurance and reinsurance balances payable					7,795	7,795	7,243
Accounts payable, accrued expenses, and other liabilities					15,587	15,587	15,004
Deferred tax liabilities					292	292	389
Total liabilities					148,604	148,604	140,340
Stockholders' Equity					50,540	50,540	59,714	59,441
Liabilities and Equity					199,144	199,144	200,054
Business Combination, Integration Related Costs						48	0	0
Revenues						43,166	40,963	35,994
Net income						5,313	8,539	3,533
Net premiums earned						40,389	36,355	$ 33,117
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets					2,459	2,459	2,508
Indefinite-lived intangible assets,					2,982	2,982	2,947
Total identified intangible assets					5,441	$ 5,441	5,455
Huatai Group [Member]
Business Acquisitions [Line Items]
Equity method investment, additional 31.8 percent agreed on						31.80%
Purchase of incremental ownership interest						$ 2,000
Deposits Assets					184	$ 184	1,100
Payment to acquire additional ownership interest in equity method investment				$ 500
Equity method investment, additional 7.1 percent agreed on				7.05%
Equity Method Investment, 83.2 percent agreed on						83.20%
Huatai Group [Member] | Subsequent Event [Member]
Business Acquisitions [Line Items]
Equity method investment, additional 22.0 percent agreed on		22.00%
Equity method investment, outstanding 3.0 percent requiring regulatory approval		3.00%
Cigna's Life Insurance Business in Asian Markets
Business Acquisitions [Line Items]
Business Acquisition, Effective Date of Acquisition			Jul. 01, 2022
Payments to Acquire Businesses, Gross			$ 5,400
Goodwill			1,250
Other intangible assets			309
Value of business acquired			3,503
Repurchase agreements			2,000
Investments and Cash			5,275
Accrued investment income			33
Insurance and reinsurance balances receivable			52
Reinsurance recoverable on losses and loss expenses			3
Reinsurance recoverable on policy benefits			82
Goodwill			1,559
Other assets			649
Total assets			11,156
Unpaid losses and loss expenses			12
Unearned premiums			59
Future policy benefits			3,817
Insurance and reinsurance balances payable			115
Accounts payable, accrued expenses, and other liabilities			924
Deferred tax liabilities			870
Total liabilities			5,797
Stockholders' Equity			5,359
Liabilities and Equity			11,156
Revenues					1,507
Net income					$ 148
Finite-Lived Intangible Assets [Line Items]
Total identified intangible assets			309
Cigna's Life Insurance Business in Asian Markets | Pro Forma
Business Acquisitions [Line Items]
Net premiums earned						$ 41,913	39,495
Business Acquisition, Pro Forma Revenue						44,673	44,166
Business Acquisition, Pro Forma Net Income (Loss)						$ 5,503	$ 8,921
Direct Ownership [Member] | Huatai Group [Member]
Business Acquisitions [Line Items]
Ownership Percentage					47.30%	47.30%
Equity method investment, ownership percentage upon completion					86.10%	86.10%
Direct Ownership [Member] | Huatai Group [Member] | Subsequent Event [Member]
Business Acquisitions [Line Items]
Ownership Percentage		64.20%
Trademarks | Cigna's Life Insurance Business in Asian Markets
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets,			70
Agency distribution relationships and renewal rights | Cigna's Life Insurance Business in Asian Markets
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets			$ 230
Finite-lived intangible assets, weighted average useful life			22 years
Unearned premium reserves intangible asset | Cigna's Life Insurance Business in Asian Markets
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets			$ 9
Finite-lived intangible assets, weighted average useful life			1 year

[1] Net of valuation allowance for uncollectible reinsurance.