Represents the revenue recognized from the sale of linaclotide API.

No definition available.

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- Definition

Represents the revenue recognized in commercial launch milestones.

+ References

No definition available.

+ Details

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- Definition

Represents the value of the contingent equity investment asset recorded at the inception of the collaborative agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the maximum contingent equity investment that may be received if certain milestones are achieved.

+ References

No definition available.

+ Details

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- Definition

Represents the maximum contingent equity and milestone payments that may be received if certain milestones are achieved.

+ References

No definition available.

+ Details

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- Definition

Represents the milestone payments received.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the milestone payments received, net of foreign withholding taxes.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents the amount of each milestone payment to be received by the company upon each of the first commercial drug launches in each of the five major E.U. countries.

+ References

No definition available.

+ Details

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- Definition

Number of prospective major European union countries for which first commercial drug launch is covered in the collaborative agreement.

+ References

No definition available.

+ Details

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- Definition

Number of major European union countries for which first commercial drug launch has occurred in connection with the collaborative agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the number of milestones achieved under the collaboration agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Represents the amount of payment received for each milestone, net of foreign tax withholdings.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the total potential amounts of milestone payment to be received by the entity upon commercial launch milestones for all major countries.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents the non-refundable up-front payment received net of foreign withholding taxes.

+ References

No definition available.

+ Details

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Namespace Prefix:	irwd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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- Definition

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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- Definition

Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 14

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- Definition

Cash received from licensees for license fees during the current period.

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-SubTopic 10

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Number of new stock issued during the period.

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-Name Regulation S-X (SX)

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Collaboration and License Agreements (Details 2) (USD $)	3 Months Ended		1 Months Ended		3 Months Ended	45 Months Ended	0 Months Ended	1 Months Ended	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	May 31, 2009	Apr. 30, 2009	Jun. 30, 2013 item	Dec. 31, 2012	Nov. 13, 2009	Nov. 30, 2010	Jun. 30, 2014	Feb. 28, 2014
Collaboration and License Agreements
Total collaborative arrangements revenue	$ 28,932,000us-gaap_Revenues	$ 14,605,000us-gaap_Revenues
Collaborative arrangement
Collaboration and License Agreements
Total collaborative arrangements revenue	2,300,000
Almirall, S.A.
Collaboration and License Agreements
Up-front fee received, net			38,000,000
Up-front fee received			40,000,000			6,000,000
Asset value for contingent equity investment by collaborative party recorded at inception of agreement				6,000,000
Incremental deferred revenue related to contingent equity investment				6,000,000
Milestone payment due upon the first commercial launch in each of the five major European Union countries	4,000,000
Number of major European Union countries	5				5
Number of major European Union countries in which commercial launch occurred					2
Total collaborative arrangements revenue	101,000	4,481,000
Revenue recognized from sale of API		3,400,000
Revenue recognized in commercial launch milestones		1,000,000
Almirall, S.A. \| Convertible preferred stock (Note 11)
Collaboration and License Agreements
Equity investment in the entity's capital stock							15,000,000
Issuance of Convertible preferred stock (in shares)							681,819
Almirall, S.A. \| Development and sales milestones
Collaboration and License Agreements
Maximum contingent equity and milestone payments to be received				40,000,000
Almirall, S.A. \| Development milestones
Collaboration and License Agreements
Milestone payment received, net of foreign withholding taxes								19,000,000
Milestone payment received								20,000,000
Total milestone payment due upon the first commercial launch in all major European Union countries					17,000,000					17,000,000
Almirall, S.A. \| Development milestones \| Convertible preferred stock (Note 11)
Collaboration and License Agreements
Contingent equity investment to be received form forward purchase contract				15,000,000
Almirall, S.A. \| Amended Development Milestones
Collaboration and License Agreements
Milestone payment received, net of foreign withholding taxes					1,900,000				1,000,000
Milestone payment received		1,000,000							1,000,000
Number of milestones achieved under collaboration agreement					2
Milestones, net of foreign tax withholdings					1,000,000				$ 1,000,000