Fair Value Measurements - Fair Value Disclosures for Financial Instruments Not Carried at Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair Value \| Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including current maturities, excluding finance leases	$ 28,033	$ 28,653
Fair Value \| Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commercial mortgage loans		1,491
Commercial mortgage loans, including assets held for sale	1,430
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Commercial mortgage loans		1,614
Long-term debt, including current maturities, excluding finance leases	29,585	$ 30,994
Commercial mortgage loans, including assets held for sale	$ 1,533

Mortgage Loans on Real Estate, Commercial and Consumer, Net, Before Reclassification To Disposal Group Assets Held For Sale

No definition available.

+ Details

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Namespace Prefix:	ci_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

No definition available.

+ Details

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

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