Debt Instrument, Required Quarterly Payments, Percentage Of Principal

No definition available.

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Period Type:	instant

- Definition

Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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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+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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Period Type:	duration

- Definition

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.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for a borrowing supported by a written promise to pay an obligation.

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=hum_GentivaTermLoanDue2025Member
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Balance Type:
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- Details

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- Details

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- Details

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- Details

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- Details

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DEBT - Credit Agreement and Term Loan Agreement (Details) - USD ($)			1 Months Ended	9 Months Ended
	Oct. 29, 2021	Aug. 17, 2021	Aug. 31, 2021	Sep. 30, 2021	Sep. 30, 2020
Line of Credit Facility [Line Items]
Repayment of term loan				$ 150,000,000	$ 0
Revolving credit facility \| Gentiva
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 350,000,000
Borrowings outstanding		$ 0
Term loan \| Gentiva term loan, due July 2, 2025
Line of Credit Facility [Line Items]
Repayment of term loan			$ 150,000,000
Required quarterly amortization payments as percentage of principal		0.25%
Term loan \| Gentiva term loan, due July 2, 2025 \| Subsequent event
Line of Credit Facility [Line Items]
Repayment of term loan	$ 1,900,000,000
Term loan \| Gentiva term loan, due July 2, 2025 \| Base rate
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)		1.75%
Term loan \| Gentiva term loan, due July 2, 2025 \| Eurodollar
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)		2.75%
Term loan \| October 2021 Term Loan Agreement \| Subsequent event
Line of Credit Facility [Line Items]
Aggregate principal	$ 2,000,000,000
Kindred at Home
Line of Credit Facility [Line Items]
Debt assumed in acquisition		$ 2,078,000,000