Acquisitions (Pro forma) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Business Acquisition [Line Items]
Net premiums earned	$ 10,142	$ 8,737
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] \| Pro Forma
Business Acquisition [Line Items]
Net premiums earned		9,512
Total revenues		10,417
Net income		$ 2,059

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.

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

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