Acquisitions (Pro forma) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Net premiums earned	$ 45,712	$ 40,360	$ 36,292
Cigna's Life Insurance Business in Asian Markets \| Pro Forma
Business Acquisition [Line Items]
Net premiums earned		41,884	39,432
Total revenues		44,605	44,072
Business Acquisition, Pro Forma Net Income (Loss)		5,533	$ 8,906
Huatai Group [Member] \| Pro Forma
Business Acquisition [Line Items]
Net premiums earned	46,502	41,903
Total revenues	50,550	44,936
Business Acquisition, Pro Forma Net income (loss), Including Portion Attributable to Noncontrolling Interests	8,850	5,290
Business Acquisition, Pro Forma Net Income (Loss)	$ 8,859	$ 5,267

Business Acquisition, Pro Forma Net income (loss), Including Portion Attributable to Noncontrolling Interests

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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