Debt Instrument Basis Margin

No definition available.

Name:	hnt_DebtInstrumentBasisMargin
Namespace Prefix:	hnt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Draw On Outstanding Letters Of Credit Amount

+ References

No definition available.

+ Details

Name:	hnt_DrawOnOutstandingLettersOfCreditAmount
Namespace Prefix:	hnt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Interest Period for Credit Facility

+ References

No definition available.

+ Details

Name:	hnt_InterestPeriodforCreditFacility
Namespace Prefix:	hnt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Limit Of Uninsured Judgment Not Stayed Period

+ References

No definition available.

+ Details

Name:	hnt_LimitOfUninsuredJudgmentNotStayedPeriod
Namespace Prefix:	hnt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Limit of uninsured judgment not stayed within 60 days.

+ References

No definition available.

+ Details

Name:	hnt_LimitOfUninsuredJudgmentNotStayedWithin60Days
Namespace Prefix:	hnt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Threshold Amount for Noncompliance with line of credit agreement.

+ References

No definition available.

+ Details

Name:	hnt_LineOfCreditDefaultLimit
Namespace Prefix:	hnt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Additional amount that may be borrowed under the credit facility.

+ References

No definition available.

+ Details

Name:	hnt_LineOfCreditFacilityIncreaseAdditionalBorrowingCapacity
Namespace Prefix:	hnt_
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.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
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.

+ 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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ 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))

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateDescription
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_BridgeLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_StandbyLettersOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Financing Arrangements (Revolving Credit Facility and Letters of Credit) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Oct. 31, 2011
Debt Instrument [Line Items]
Maximum amount available for borrowing under the revolving credit facility			$ 600,000,000
Line of credit facility, maturity date	Oct. 24, 2016
Additional borrowing capacity			200,000,000
Revolving credit facility outstanding balance	195,000,000us-gaap_LineOfCredit
Revolving credit facility, remaining capacity	398,500,000	491,400,000
Line of credit default limit	50,000,000hnt_LineOfCreditDefaultLimit
Limit of uninsured judgment not stayed within 60 days	50,000,000
Limit of uninsured judgment not stayed, period (in days)	60 days
Standby Letters of Credit [Member]
Debt Instrument [Line Items]
Revolving credit facility, borrowing capacity			400,000,000
Letter of Credit [Member]
Debt Instrument [Line Items]
Maximum amount available for borrowing under the revolving credit facility			400,000,000
Outstanding letters of credit	6,500,000	8,600,000
Amounts drawn on letters of credit	0	0
Bridge Loan [Member]
Debt Instrument [Line Items]
Maximum amount available for borrowing under the revolving credit facility			$ 50,000,000
Line of Credit [Member]
Debt Instrument [Line Items]
Debt instrument basis description	a) the base rate (which is a rate per annum equal to the greatest of (i) the federal funds rate plus one-half of one percent, (ii) Bank of America, N.A.’s “prime rate” and (iii) the Eurodollar Rate (as such term is defined in the credit facility) for a one-month interest period plus one percent) plus an applicable margin ranging from 45 to 105 basis points or (b) the Eurodollar Rate plus an applicable margin ranging from 145 to 205 basis points
Line of Credit [Member] \| Federal Funds [Member] \| Variable Base Rate A [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percentage)	0.50%
Line of Credit [Member] \| Eurodollar Rate Plus 45 to 105 Basis Points [Member] \| Variable Base Rate A [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread (as a percentage)	1.00%
Interest period on credit facility (in months)	1 month
Line of Credit [Member] \| Eurodollar Rate Plus 45 to 105 Basis Points [Member] \| Variable Base Rate A [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percentage)	0.45%
Line of Credit [Member] \| Eurodollar Rate Plus 45 to 105 Basis Points [Member] \| Variable Base Rate A [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percentage)	1.05%
Line of Credit [Member] \| Eurodollar Rate Plus 145 to 205 Basis Points [Member] \| Variable Base Rate B [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percentage)	1.45%
Line of Credit [Member] \| Eurodollar Rate Plus 145 to 205 Basis Points [Member] \| Variable Base Rate B [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate (as a percentage)	2.05%