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Equity Method Investment, Outstanding 22.0 Percent Agreed On

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Equity method investment, outstanding 3.0 percent requiring regulatory approval

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Equity Method Investment, Outstanding payment to be made

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Date when the acquirer obtains control of the acquiree, in YYYY-MM-DD format.

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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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 cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount, after accumulated amortization, of present value of future profits of insurance contract acquired in business combination.

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Acquisitions (Investment holdings) (Details) - USD ($) $ in Millions			3 Months Ended		12 Months Ended
	Jan. 31, 2023	Jul. 01, 2022	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Business Acquisition [Line Items]
Goodwill			$ 16,175		$ 16,228
Other intangible assets			5,364		5,441
Value of business acquired (preliminary)			3,603		3,702
Repurchase agreements			1,420		1,419
Cigna integration expenses			22	$ 0
Huatai Group
Business Acquisition [Line Items]
Equity method investment, outstanding 22.0 percent agreed on	22.00%
Equity method investment, outstanding 3.0 percent requiring regulatory approval	3.00%
Equity Method Investment, Outstanding payment to be made			800
Equity method investment, additional 31.8 percent agreed on					$ 567
Cigna's Life Insurance Business in Asia-Pacific Markets [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition		Jul. 01, 2022
Payments to Acquire Businesses, Gross		$ 5,400
Goodwill		1,177
Other intangible assets		309
Value of business acquired (preliminary)		3,633
Repurchase agreements		$ 2,000
Cigna integration expenses			$ 22
Direct ownership \| Huatai Group
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage			64.20%		47.30%