Amount by which Company may increase the term length of the credit agreement.

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Debt Instrument, Term-Out Option, Term After Conversion Election

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Gain (Loss) On Extinguishment Of Debt, Net Of Tax

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The debt-to adjusted capital ratio which the Company must not exceed in accordance with the terms of the line of credit facility agreement.

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Number of banks participating in revolving credit and letter of credit agreement

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Average rate paid on commercial paper.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Regulation S-K (SK)
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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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Face (par) amount of the original debt instrument that was repurchased.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Schedule I - Condensed Financial Information of Cigna Corporation - Debt (Details)	1 Months Ended	2 Months Ended	12 Months Ended
	Apr. 30, 2021 USD ($) bank	Apr. 30, 2020 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Aggregate principal amount of outstanding debt securities redeemed			$ 4,500,000,000
Debt extinguishment costs			141,000,000	$ 199,000,000	$ 2,000,000
Loss on repurchase of debt, after-tax			$ 110,000,000
Commercial paper average interest rate			0.26%
Commercial Paper
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 5,000,000,000
Revolving Credit and Letter of Credit Facility Maturing April 2026, Revolving Credit and Letter of Credit Facility Maturing April 2024, and 364 Day Revolving Credit Agreement Maturing April 2022
Debt Instrument [Line Items]
Outstanding balances			$ 0
Aggregate amount of options to increase commitments	$ 1,500,000,000
Five-year Revolving Credit Agreement, Maturing April 2026
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 3,000,000,000
Credit agreement term	5 years
Number of participating banks \| bank	23
Amount by which credit facility term length can be increased	1 year
Leverage ratio covenant	60.00%
Five-year Revolving Credit Agreement, Maturing April 2026 \| Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000,000
Three-year Revolving Credit Agreement, Maturing April 2024
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,000,000,000
Credit agreement term	3 years
Number of participating banks \| bank	23
Amount by which credit facility term length can be increased	1 year
Leverage ratio covenant	60.00%
364-day Revolving Credit Agreement, Maturing April 2022
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,000,000,000
Credit agreement term	364 days
Number of participating banks \| bank	23
Term of borrowing after exercising the "term out" option	1 year
Leverage ratio covenant	60.00%
Five-year Revolving Credit Agreement, Maturing April 2023
Debt Instrument [Line Items]
Credit agreement term			5 years
364-day Revolving Credit Agreement, Maturing October 2021
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,000,000,000
Credit agreement term	364 days
Cigna
Debt Instrument [Line Items]
Aggregate principal amount of outstanding debt securities redeemed			$ 4,200,000,000
Debt extinguishment costs		$ 131,000,000	$ 131,000,000	$ 171,000,000	$ 0
Loss on repurchase of debt, after-tax		$ 101,000,000
Commercial paper average interest rate			0.26%
Cigna \| Commercial Paper
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 5,000,000,000
Cigna \| Revolving Credit and Letter of Credit Facility Maturing April 2026, Revolving Credit and Letter of Credit Facility Maturing April 2024, and 364 Day Revolving Credit Agreement Maturing April 2022
Debt Instrument [Line Items]
Outstanding balances			$ 0
Aggregate amount of options to increase commitments	$ 1,500,000,000
Cigna \| Five-year Revolving Credit Agreement, Maturing April 2026
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 3,000,000,000
Credit agreement term	5 years
Number of participating banks \| bank	23
Amount by which credit facility term length can be increased	1 year
Leverage ratio covenant	60.00%
Cigna \| Five-year Revolving Credit Agreement, Maturing April 2026 \| Letter of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000,000
Cigna \| Three-year Revolving Credit Agreement, Maturing April 2024
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,000,000,000
Credit agreement term	3 years
Number of participating banks \| bank	23
Amount by which credit facility term length can be increased	1 year
Leverage ratio covenant	60.00%
Cigna \| 364-day Revolving Credit Agreement, Maturing April 2022
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,000,000,000
Credit agreement term	364 days
Number of participating banks \| bank	23
Term of borrowing after exercising the "term out" option	1 year
Leverage ratio covenant	60.00%
Cigna \| Five-year Revolving Credit Agreement, Maturing April 2023
Debt Instrument [Line Items]
Credit agreement term			5 years
Cigna \| 364-day Revolving Credit Agreement, Maturing October 2021
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,000,000,000
Credit agreement term	364 days