Note 10 - Debt (Details Textual) - Revolving Credit Facility [Member] - Truist Bank [Member] - USD ($) $ in Thousands	Oct. 28, 2020	Sep. 30, 2022
Debt Instrument, Covenant, Maximum Funded Debt Leverage Ratio	3.0
Debt Instrument, Covenant, Interest Coverage Ratio	3.0
Long-Term Line of Credit, Total		$ 0
Minimum [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.20%
Maximum [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.30%
Third Amendment [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 65,000
Line of Credit Facility, Increased Facility Size Due to Accordion Feature	$ 25,000
Third Amendment [Member] \| Fed Funds Effective Rate Overnight Index Swap Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Third Amendment [Member] \| Base Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Third Amendment [Member] \| Base Rate [Member] \| Minimum [Member]
Line of Credit Facility, Percentage of Applicable Margin for Borrowings	0.50%
Third Amendment [Member] \| Base Rate [Member] \| Maximum [Member]
Line of Credit Facility, Percentage of Applicable Margin for Borrowings	0.75%
Third Amendment [Member] \| Eurodollar [Member] \| Minimum [Member]
Line of Credit Facility, Percentage of Applicable Margin for Borrowings	1.50%
Third Amendment [Member] \| Eurodollar [Member] \| Maximum [Member]
Line of Credit Facility, Percentage of Applicable Margin for Borrowings	1.75%
Third Amendment [Member] \| Swing Line Subfacility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 5,000
Third Amendment [Member] \| Letter of Credit Subfacility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 5,000

Represents the minimum requirement for interest coverage ratio under the debt agreement.

No definition available.

Name:	hstm_DebtInstrumentCovenantInterestCoverageRatio
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- Definition

Requirement for maximum funded debt ratio (consolidated debt/consolidated EBITDA) under the debt agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the increased line of credit facility size due to accordion feature.

+ References

No definition available.

+ Details

Name:	hstm_LineOfCreditFacilityIncreasedFacilitySizeDueToAccordionFeature
Namespace Prefix:	hstm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the applicable margin percentage for borrowings under a line of credit facility.

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

+ Details

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

- 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

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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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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- Details

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- Details

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- Details

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