The total amount of capital expenditures permitted annually.

No definition available.

Name:	hls_Capitalexpenditurespermitted
Namespace Prefix:	hls_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum leverage ratio in the financial covenants in the company's credit agreement.

+ References

No definition available.

+ Details

Name:	hls_FinancialCovenantsLeverageRatioMaximum
Namespace Prefix:	hls_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Long Term Debt.

+ References

No definition available.

+ Details

Name:	hls_LongTermDebtTextualAbstract
Namespace Prefix:	hls_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of cash drawn on the Company's revolving line of credit.

+ References

No definition available.

+ Details

Name:	hls_RevolverAmountsDrawn
Namespace Prefix:	hls_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Par value of debt instrument issued plus or minus a premium or a discount.

+ References

No definition available.

+ Details

Name:	hls_SeniorNoteIssuePrice
Namespace Prefix:	hls_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of cash received from a Senior Notes isssuance and ultimately used to reduce principal amounts of the Company's other debt instruments.

+ References

No definition available.

+ Details

Name:	hls_SeniorNotesIssuanceProceedsUsedForDebtReduction
Namespace Prefix:	hls_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

A portion of the principal amount of Senior Notes extinguished.

+ References

No definition available.

+ Details

Name:	hls_SeniorNotesPortionofPrincipalExtinguishedCommitment
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

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

- Definition

The amount of cash received by the Company from a debt issuance of Senior Notes in a private offering.

+ References

No definition available.

+ Details

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

- Definition

The amount of cash received by the Company from a debt issuance of Senior Notes to the public.

+ References

No definition available.

+ Details

Name:	hls_SeniorNotesProceedsFromPublicOffering
Namespace Prefix:	hls_
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

Name:	hls_SeniorNotesRedemptionPriceExpressedAsPercentageOfPrincipal
Namespace Prefix:	hls_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum borrowing capacity under the term loan facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

No definition available.

+ Details

Name:	hls_TermLoanFacilityMaximumBorrowingCapacity
Namespace Prefix:	hls_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity.

+ References

No definition available.

+ Details

Name:	hls_TermloanfacilityUnusedBorrowingCapacityAmount
Namespace Prefix:	hls_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amounts drawn on term loan facility.

+ References

No definition available.

+ Details

Name:	hls_Termloanfacilitydraw
Namespace Prefix:	hls_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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 55

-Paragraph 8

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

Reference 2: 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

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ 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(b))

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

+ Details

Name:	us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

+ Details

Name:	us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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

+ Details

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

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially 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 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 FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16(a))

-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 19, 20, 22

-Article 5

+ Details

Name:	us-gaap_LoansPayableToBank
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

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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

+ Details

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

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

Name:	us-gaap_LongtermDebtTypeAxis=hls_SeniorNotes08125Due2020Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=hls_SeniorNotes0775Due2022Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=hls_SeniorNotes05.125Due2023Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=hls_SeniorNotes0575Due2024Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=hls_SeniorNotes05.75Due2025Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=hls_A2.00ConvertibleSeniorSubordinatedNotesdue2043Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Long-term Debt - Textual (Details) $ in Millions			1 Months Ended	3 Months Ended						9 Months Ended
Long-term Debt - Textual (Details) $ in Millions	Oct. 28, 2015 USD ($)	Apr. 10, 2015 USD ($)	Jan. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Jul. 01, 2017	Jun. 30, 2017	Sep. 01, 2015 USD ($)	Aug. 31, 2015 USD ($)	Jul. 29, 2015 USD ($)	Jul. 28, 2015	Jun. 24, 2015 USD ($)	Jun. 23, 2015 USD ($)
Long Term Debt (Textual) [ Abstract]
Loss on early extinguishment of debt					$ 0.0	$ 18.8	$ 1.2		$ 0.0	$ 20.0	$ 0.0
Repayments of Long-term Debt										546.3	$ 5.7
Capital expenditures, permitted																		$ 350.0	$ 200.0
Financial Covenants Leverage Ratio, Maximum																4.50	4.25
Subsequent Event [Member]
Long Term Debt (Textual) [ Abstract]
Financial Covenants Leverage Ratio, Maximum													4.50
Term Loan Facilities [Member]
Long Term Debt (Textual) [ Abstract]
Term loan facility, draw					125.0			$ 375.0		125.0
Term Loan Facility, Maximum Borrowing Capacity																$ 500.0
Term loan facilities					$ 320.0			450.0		$ 320.0						195.0
Term loan facility, Unused Borrowing Capacity, Amount														$ 250.0
Revolving Credit Facility [Member]
Long Term Debt (Textual) [ Abstract]
Revolver, Amounts Drawn								$ 325.0
Line of Credit Facility, Maximum Borrowing Capacity																$ 600.0
8.125% Senior Notes Due 2020 [Member]
Long Term Debt (Textual) [ Abstract]
Senior Note, redemption price		104.063%
Repayments of Long-term Debt		$ 302.0
Senior Notes, Principal Extinguished		$ 290.0
Debt Instrument, Interest Rate, Stated Percentage					8.125%					8.125%
7.75% Senior Notes Due 2022 [Member]
Long Term Debt (Textual) [ Abstract]
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	103.875%
Senior Notes, Portion of Principal Extinguished	$ 50.0
5.125% Senior Notes Due 2023 [Member]
Long Term Debt (Textual) [ Abstract]
Debt issuance, face amount							$ 300.0
Senior Note, issue price							100.00%
Senior Notes, proceeds from public offering							$ 295.0
Debt Instrument, Interest Rate, Stated Percentage					5.125%					5.125%
5.75% Senior Notes Due 2024 [Member]
Long Term Debt (Textual) [ Abstract]
Debt issuance, face amount			$ 400.0												$ 350.0
Senior Note, issue price			102.00%												100.50%
Senior Notes Issuance, Proceeds Used For Debt Reduction			$ 250.0
Senior Notes, Proceeds From Private Offering															$ 351.0
Debt Instrument, Interest Rate, Stated Percentage					5.75%					5.75%
5.75% Senior Notes Due 2025 [Member]
Long Term Debt (Textual) [ Abstract]
Debt issuance, face amount					$ 350.0					$ 350.0
Senior Note, issue price					100.00%					100.00%
Senior Notes, Proceeds From Private Offering					$ 344.0					$ 344.0
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]
Loss on early extinguishment of debt				$ 2.0
Repayments of Long-term Debt	$ 52.0
Financial Covenants Leverage Ratio, Maximum												4.25
Scenario, Forecast [Member] \| Term Loan Facilities [Member]
Long Term Debt (Textual) [ Abstract]
Term loan facility, capacity				$ 125.0