Assets and Liabilities of Businesses Held for Sale (Details) - Medicare Advantage and related Cigna Healthcare businesses - Held-for-Sale - USD ($) $ in Millions	Mar. 31, 2024	Jan. 31, 2024	Dec. 31, 2023
Disposal Group, Including Discontinued Operation, Balance Sheet Disclosures [Abstract]
Cash and cash equivalents	$ 1,660		$ 467
Investments	1,341		1,438
Accounts receivable, net	959		1,122
Other assets, including Goodwill	2,394		2,963
Goodwill classified as Assets of businesses held for sale	396		396
Total assets of businesses held for sale	6,354		5,990
Insurance and contractholder liabilities	2,081		1,636
All other liabilities	1,134		1,059
Total liabilities of businesses held for sale	$ 3,215		$ 2,695
Health Care Service Corporation (HCSC)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale price		$ 3,300

Disposal Group,Including Discontinued Operation, Insurance And Contractholder Liabilities

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Disposal Group, Including Discontinued Operation, Investments

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Goodwill and amount classified as other assets attributable to disposal group held for sale or disposed of.

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.

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Amount classified as cash and cash equivalents attributable to disposal group held for sale or disposed of.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Amount classified as liabilities attributable to disposal group held for sale or disposed of.

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