Commitments and Contingencies (Details)	9 Months Ended
Sep. 30, 2025 USD ($) covenant	Dec. 31, 2024 USD ($)
Short-term Debt [Line Items]
Bank line of credit	$ 300,000,000.0
Basis spread on variable rate	1.65%
Line of credit	$ 0	$ 0
Financial covenants \| covenant	2
Reduction of bank line of credit	$ 48,000,000.0
Amount available under line of credit	252,000,000.0
Irrevocable standby letters of credit
Short-term Debt [Line Items]
Irrevocable standby letter of credit, outstanding	48,000,000.0
Revolving Credit Facility \| Unsecured Revolving Loan Facility \| Line of Credit
Short-term Debt [Line Items]
Bank line of credit	$ 300,000,000
Expiration period	5 years
Additional commitment	$ 500,000,000.0

Debt Instrument, Covenant, Number

No definition available.

Name:	hcsg_DebtInstrumentCovenantNumber
Namespace Prefix:	hcsg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option

+ References

No definition available.

+ Details

Name:	hcsg_LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption
Namespace Prefix:	hcsg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Facility, Increase (Decrease) Remaining Borrowing Capacity

+ References

No definition available.

+ Details

Name:	hcsg_LineOfCreditFacilityIncreaseDecreaseRemainingBorrowingCapacity
Namespace Prefix:	hcsg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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:	dtr-types:percentItemType
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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 605
-Name Accounting Standards Codification
-Section 55
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477548/944-605-55-15

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+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Topic 210
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-Subparagraph (SX 210.9-03(16))
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+ Details

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

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SX 210.5-02(22)(b))
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+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Subparagraph (b)
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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