Acquisitions (Pro forma) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Business Acquisition [Line Items]
Net premiums earned	$ 10,999	$ 9,549	$ 21,141	$ 18,286
Cigna's Life Insurance Business in Asia-Pacific Markets [Member] \| Pro Forma
Business Acquisition [Line Items]
Net premiums earned		10,299		19,811
Total revenues		10,620		21,037
Net income		$ 1,276		$ 3,335

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.

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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.

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

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