Number of members eligible for the health care programs.

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Health Plan, Contract Term

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Number of Members Covered

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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

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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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Organization and Basis of Presentation (Details) member in Thousands, $ in Millions		1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 22, 2021 USD ($)	Sep. 30, 2020 USD ($)	Mar. 31, 2021 USD ($) member	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) member
Segment Reporting Information [Line Items]
Premium revenue			$ 6,306	$ 4,304
Cigna Corporation's Texas Medicaid and Medicare-Medicaid Plan
Segment Reporting Information [Line Items]
Premium revenue					$ 1,000
Cigna Corporation's Texas Medicaid and Medicare-Medicaid Plan \| Hidalgo, Tarrant and Northeast Service Areas
Segment Reporting Information [Line Items]
Number of members covered \| member					48
Cigna Corporation's Texas Medicaid and Medicare-Medicaid Plan \| Hidalgo Service Area
Segment Reporting Information [Line Items]
Number of members covered \| member					2
Cigna Corporation's Texas Medicaid and Medicare-Medicaid Plan \| Subsequent event
Segment Reporting Information [Line Items]
Total Purchase price	$ 60
Affinity health plan
Segment Reporting Information [Line Items]
Net cash paid in business combinations		$ 380
Health Plans
Segment Reporting Information [Line Items]
Number of members eligible for the health care programs, approximately \| member			4,600
Minimum \| Health Plans
Segment Reporting Information [Line Items]
Contract term			3 years
Maximum \| Health Plans
Segment Reporting Information [Line Items]
Contract term			5 years