No definition available.

Name:	us-gaap_GainLossRelatedToLitigationSettlementAbstract
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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

+ Details

Name:	us-gaap_LitigationReserve
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Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position.

+ References

+ Details

Name:	us-gaap_LitigationReserveCurrent
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Data Type:	xbrli:monetaryItemType
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- References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementAbstract
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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

+ Details

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

- Definition

Amount of loss from litigation settlement for amount awarded to other party. Excludes claims within an insurance entity's normal claims settlement process.

+ References

+ Details

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

- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 25
-Subparagraph (g)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-25

+ Details

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- Details

Name:	srt_LitigationCaseAxis=irwd_FerringInternationalCenterSaComplaintAgainstVectivbioAgFerringSettlementAgreementWithEntityMember
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Period Type:

Collaboration, License, and Other Agreements - Litigation (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Dec. 18, 2025	Dec. 31, 2025	Dec. 31, 2025	Jun. 30, 2026
Litigation Settlement
Accrued litigation settlement		$ 5,000	$ 5,000	$ 5,000
Ferring International Center S.A. Complaint Against VectivBio AG, Ferring Settlement Agreement with Entity
Litigation Settlement
Litigation settlement, amount awarded to other party	$ 12,500
Payments for legal settlements		$ 7,500
Estimated litigation liability				5,000
Accrued litigation settlement				$ 5,000
Gain (Loss) from Litigation Settlement
Litigation settlement, loss, recorded in selling, general, and administrative expense			$ 12,500