Beneficial Owner of Common Stock, Percentage

No definition available.

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- Definition

Number Of Shares Of Preferred Stock Per Right

+ References

No definition available.

+ Details

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- Definition

Period Following the Commencement of a Tender or Exchange Offer, Days

+ References

No definition available.

+ Details

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- Definition

Period Following Determination an Individual has become a Beneficial Owner, In Days

+ References

No definition available.

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- Definition

Period Rights Seperated From Common Stock

+ References

No definition available.

+ Details

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- Definition

Right Redeemable Price

+ References

No definition available.

+ Details

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- Definition

Terms of Rights Agreement

+ References

No definition available.

+ Details

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i)(4))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Period Type:	instant

- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ 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 210.5-02.29)

-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 30

-Article 5

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-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 30

-Article 5

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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Balance Type:	na
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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ 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 210.5-02.28)

-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

-Article 5

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Balance Type:	na
Period Type:	instant

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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

- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

+ 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 210.5-02.28,29)

-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 29, 30

-Article 5

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

+ Details

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

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-Subparagraph (SX 210.3-04)

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-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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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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Capital Stock (Details) (USD $)	0 Months Ended		12 Months Ended
Capital Stock (Details) (USD $)	Aug. 07, 2006	Aug. 07, 2006	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 16, 2014	Mar. 08, 2012	May 31, 2011	May 02, 2011
Equity, Class of Treasury Stock [Line Items]
Common stock, shares issued			152,451,000us-gaap_CommonStockSharesIssued	150,224,000us-gaap_CommonStockSharesIssued
Treasury stock, shares			74,378,000us-gaap_TreasuryStockShares	70,704,000us-gaap_TreasuryStockShares
Common stock, outstanding			78,073,000us-gaap_CommonStockSharesOutstanding
Purchase rate of rights		0.001
Preferred stock, par value (usd per share)	$ 0.001	$ 0.001	$ 0.001	$ 0.001
Purchase price, per right	$ 170.00	$ 170.00
Period rights separated from common stock	10 days
Period following the commencement of a tender or exchange offer	10 days
Period following determination an individual has become a beneficial owner	10 days
Price per redeemable right	0.01hnt_RightRedeemablePrice
Stock repurchase program authorized amount						$ 257,800,000.0	$ 323,700,000.0	$ 300,000,000
Treasury stock value acquired cost method			161,908,000	87,119,000	69,496,000
Stock repurchase program remaining authorized repurchase amount			400,000,000	280,000,000		400,000,000
Benefical Owner of Common Stock Percentage [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement	15.00%
Beneficial owner of common stock, percentage	15.00%	15.00%
Percentage of Common Stock Owned [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement	10.00%
Percentage of Rights Owned By Individual Beneficial Owner Not Deemed Acquiring Person [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement	20.00%
Percentage of Assets Sold [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement	50.00%
Beneficial Owner of a Percentage of Outstanding Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement	50.00%
2011 Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program authorized amount			400,000,000.0				323,700,000.0		300,000,000
Treasury stock shares acquired			3,000,000	2,700,000
Treasury stock value acquired cost method			$ 137,800,000	$ 70,000,000