Debt Instrument, Covenant, Leverage Ratio

No definition available.

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- Definition

Debt Instrument, Covenant, Leverage Ratio, Maximum

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Unamortized Discount (Premium), Net, Reduction Due to Extinguishment of Debt

+ References

No definition available.

+ Details

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- Definition

Uncommitment incremental loan facility

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph e

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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- Definition

Amount of letters of credit outstanding under debtor-in-possession financing arrangement.

+ References

No definition available.

+ Details

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- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 2

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-Topic 470

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-Section 40

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629

+ Details

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- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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+ Details

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Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- 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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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

Amount of minimum net capital required to be maintained to engage in securities transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Rule 15c3

-Number 240

-Section 1

-Paragraph 1

-Subparagraph i

-Article 15c3

-Subsection a

+ Details

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

+ Details

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 4.E)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section E

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29-31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

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Debt - Additional Information (Detail) (USD $)	12 Months Ended	1 Months Ended		12 Months Ended		1 Months Ended
Debt - Additional Information (Detail) (USD $)	Dec. 31, 2014	Jul. 31, 2013	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2008	Oct. 31, 2014	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Percentage of senior notes principal amount which may be redeemed at our option	100.00%
Minimum level of net worth required	$ 7,800,000,000us-gaap_MinimumNetCapitalRequired1
Actual net worth	9,646,000,000us-gaap_StockholdersEquity			9,316,000,000us-gaap_StockholdersEquity			8,847,000,000us-gaap_StockholdersEquity	8,063,000,000us-gaap_StockholdersEquity
Uncommitted incremental loan facility	250,000,000hum_UncommitmentIncrementalLoanFacility
Line of credit facility, covenant terms	The terms of the credit agreement include standard provisions related to conditions of borrowing, including a customary material adverse effect clause which could limit our ability to borrow additional funds. In addition, the credit agreement contains customary restrictive and financial covenants as well as customary events of default, including financial covenants regarding the maintenance of a minimum level of net worth of $7.8 billion at December 31, 2014 and a maximum leverage ratio of 3.0:1. We are in compliance with the financial covenants, with actual net worth of $9.6 billion and actual leverage ratio of 1.4:1, as measured in accordance with the credit agreement as of December 31, 2014.
Borrowings outstanding under credit agreement	0us-gaap_LineOfCredit
Outstanding letters of credit	4,000,000
Remaining borrowing capacity	996,000,000
Prior Credit Agreement
Debt Instrument [Line Items]
Revolving credit agreement term, in years		5 years
Amount of unsecured revolving credit agreement		1,000,000,000
Senior Notes
Debt Instrument [Line Items]
Net proceeds from debt			1,730,000,000
Reduction in unamortized value adjustment of senior notes	32,000,000			54,000,000	103,000,000
Senior Notes \| $500 million, 6.45% due June 1, 2016
Debt Instrument [Line Items]
Debt redemption price, percentage						100.00%
Early redemption of debt, amount						560,000,000
Gain (loss) on extinguishment of debt						(37,000,000)
Senior notes	500,000,000			500,000,000
Debt instrument, stated interest rate	6.45%			6.45%
Reduction in unamortized value adjustment of senior notes						12,000,000
Revolving Credit Facility \| Line of Credit \| Credit Agreement
Debt Instrument [Line Items]
Maximum leverage ratios for new credit agreement	3.0
Actual net worth	9,646,000,000
Actual leverage ratio	1.4
Revolving Credit Facility \| Line of Credit \| LIBOR \| Credit Agreement
Debt Instrument [Line Items]
Basis points spread over LIBOR	1.10%
Facility fee that is dependent upon credit rating, basis points	0.15%
Revolving Credit Facility \| Line of Credit \| LIBOR \| Credit Agreement \| Minimum
Debt Instrument [Line Items]
Basis points spread over LIBOR	0.90%
Facility fee that is dependent upon credit rating, basis points	0.10%
Revolving Credit Facility \| Line of Credit \| LIBOR \| Credit Agreement \| Maximum
Debt Instrument [Line Items]
Basis points spread over LIBOR	1.50%
Facility fee that is dependent upon credit rating, basis points	25.00%
Commercial Paper
Debt Instrument [Line Items]
Amount of unsecured revolving credit agreement						1,000,000,000
Borrowings outstanding under credit agreement	$ 175,000,000