Accounting Policies - Summary of Activity to Product Returns, Distributor Fees and Discounts, Rebates and Administrative Fees (Details) $ in Thousands	9 Months Ended
Sep. 30, 2022 USD ($)
Product Information [Line Items]
Balance	$ 22,560
Provision	131,838
Payments/credits	(126,574)
Balance	27,824
Product Returns
Product Information [Line Items]
Balance	2,579
Provision	1,213
Payments/credits	(699)
Balance	3,093
Distributor Fees
Product Information [Line Items]
Balance	3,466
Provision	15,301
Payments/credits	(15,193)
Balance	3,574
Discounts, Rebates and Administrative Fees
Product Information [Line Items]
Balance	16,515
Provision	115,324
Payments/credits	(110,682)
Balance	$ 21,157

Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from provisions of amounts previously written off or reestablishment of reserves that had previously been utilized.

No definition available.

+ Details

Name:	hrtx_ValuationAllowancesAndReservesProvisions
Namespace Prefix:	hrtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Name:	us-gaap_ProductInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column B))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09(Column E))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690

+ Details

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

- Definition

Amount of decrease in valuation and qualifying accounts and reserves.

+ References

+ Details

Name:	us-gaap_ValuationAllowancesAndReservesDeductions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_ValuationAllowancesAndReservesTypeAxis=hrtx_AllowanceForSalesReturns1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ValuationAllowancesAndReservesTypeAxis=hrtx_AllowanceForDistributorFeesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ValuationAllowancesAndReservesTypeAxis=hrtx_AllowanceForRebatesAndChargebacksMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: