Name:	hum_DepreciationAndAmortizationClassifiedAsBenefitExpense
Namespace Prefix:	hum_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of member co-share amounts and government subsidies that are excluded from benefits expense because the health plans do not bear responsibility.

No definition available.

Name:	hum_GovernmentAndHealthPlanMemberSubsidiesAmount
Namespace Prefix:	hum_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Provision For Premium Deficiency

No definition available.

Name:	hum_HealthCareReformProvisionforPremiumDeficiency
Namespace Prefix:	hum_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Increase to future policy benefits payable to ensure our liability balance associated with our long-term care policies is adequate to provide for future policy benefits under these policies

No definition available.

Name:	hum_IncreaseToFuturePolicyBenefitsPayable
Namespace Prefix:	hum_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Percentage Of Total Premium And Services Revenues Derived From Contracts With The Federal Government

No definition available.

Name:	hum_PercentageOfTotalPremiumAndServicesRevenuesDerivedFromContractsWithFederalGovernment
Namespace Prefix:	hum_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

No definition available.

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.