Name:	irwd_AccruedExpensesAndOtherLiabilitiesCurrent
Namespace Prefix:	irwd_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Accrued Stock Repurchase Liability, Current

No definition available.

Name:	irwd_AccruedStockRepurchaseLiabilityCurrent
Namespace Prefix:	irwd_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- References

No definition available.

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

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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 210.5-02.20)
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_EmployeeRelatedLiabilitiesCurrent
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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_InterestPayableCurrent
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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.