Financing obligation for construction in progress.

No definition available.

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

- Definition

Long Term Debt.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Number of renewal options as part of the development/lease agreement for the new corporate headquarters.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

A portion of the principal amount of Senior Notes extinguished.

+ References

No definition available.

+ Details

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Namespace Prefix:	hls_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Gross principal amount of Senior Notes extinguished.

+ References

No definition available.

+ Details

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

- Definition

Price expressed as a percentage of principal amount at which the Company may redeem its senior notes during a specific time period in the future.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

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-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

+ Details

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

- Definition

Term of the lessee's leasing arrangement renewal, 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of the lessee's leasing arrangement, 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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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Including the current and noncurrent portions, the carrying value of notes payable which were initially due after one year or beyond the normal operating cycle, if longer, and which are not otherwise defined in the taxonomy.

+ 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 FASB
-Name Accounting Standards Codification
-Topic 944
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

+ Details

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

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ 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)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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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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- Details

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Long-term Debt - Textual (Details) $ in Millions				1 Months Ended	3 Months Ended				6 Months Ended
Long-term Debt - Textual (Details) $ in Millions	Sep. 15, 2016 USD ($)	May 06, 2016 USD ($)	Mar. 24, 2016 USD ($)	Feb. 29, 2016	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2018 USD ($)	Jul. 28, 2016 USD ($)	Apr. 06, 2016 USD ($)	Feb. 25, 2016	Feb. 23, 2016 USD ($)	Dec. 31, 2015 USD ($)
Long Term Debt (Textual) [ Abstract]
Repayments of Long-term Debt									$ 112.8	$ 546.1
Loss on early extinguishment of debt						$ 2.4	$ 2.4	$ 18.8	4.8	$ 20.0
Other notes payable						$ 43.3			$ 43.3							$ 39.2
7.75% Senior Notes Due 2022 [Member]
Long Term Debt (Textual) [ Abstract]
Senior Notes, Portion of Principal Extinguished													$ 50.0		$ 50.0
Senior Note, redemption price		103.875%	103.875%
Repayments of Long-term Debt		$ 52.0	$ 52.0
Debt Instrument, Interest Rate, Stated Percentage						7.75%			7.75%
7.75% Senior Notes Due 2022 [Member] \| Subsequent Event [Member]
Long Term Debt (Textual) [ Abstract]
Senior Note, redemption price												102.583%
Senior Notes, Principal Extinguished												$ 76.0
5.125% Senior Notes Due 2023 [Member]
Long Term Debt (Textual) [ Abstract]
Debt Instrument, Interest Rate, Stated Percentage						5.125%			5.125%
5.75% Senior Notes Due 2024 [Member]
Long Term Debt (Textual) [ Abstract]
Debt Instrument, Interest Rate, Stated Percentage						5.75%			5.75%
5.75% Senior Notes Due 2025 [Member]
Long Term Debt (Textual) [ Abstract]
Debt Instrument, Interest Rate, Stated Percentage						5.75%			5.75%
2.00% Convertible Senior Subordinated Notes due 2043 [Member]
Long Term Debt (Textual) [ Abstract]
Debt Instrument, Interest Rate, Stated Percentage						2.00%			2.00%
Scenario, Forecast [Member]
Long Term Debt (Textual) [ Abstract]
Repayments of Long-term Debt	$ 78.0
Loss on early extinguishment of debt					$ 3.0
Corporate Office
Long Term Debt (Textual) [ Abstract]
Lessee Leasing Arrangements, Operating Leases, Term of Contract				15 years
Number of renewal options														4
Lessee Leasing Arrangements, Operating Leases, Renewal Term				5 years
Construction in Progress, Increase						$ 5.8			$ 5.8
Other notes payable						$ 5.8			$ 5.8
Corporate Office \| Scenario, Forecast [Member]
Long Term Debt (Textual) [ Abstract]
Financing Obligation											$ 56.0