Amount of royalty payments if entity meets certain milestones under a research and development agreement.

No definition available.

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- Definition

Represents the additional extension period of contract manufacturing agreement.

+ References

No definition available.

+ Details

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- Definition

Aggregate additional series of contingent milestone payments if selects to develop for second indication.

+ References

No definition available.

+ Details

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- Definition

Collaborative Arrangement, Milestone Payment

+ References

No definition available.

+ Details

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- Definition

Amount of upfront payment paid during the period under collaborative arrangement.

+ References

No definition available.

+ Details

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- Definition

Represents the period prior to the expiration of the agreement in which an agreement for extension may be entered into upon mutual agreement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Represents the minimum obligation due under the terms of the agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Future Milestone Payments

+ References

No definition available.

+ Details

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

Represents the initial period of contract manufacturing agreement.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Manufacture And Supply Agreement, Estimated Costs

+ References

No definition available.

+ Details

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

Aggregate payment upon the achievement of certain clinical milestones.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Period for meeting sales milestones for additional royalty payments after the drug is commercialized.

+ References

No definition available.

+ Details

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- Definition

Represents the period of each automatic renewal of contract manufacturing agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the written notice period required for termination of contract manufacturing agreement by either party.

+ References

No definition available.

+ Details

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- 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

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- Definition

The amount of cash paid for royalties during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 230
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-Section 45
-Paragraph 25
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- Definition

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount the entity has committed to make for future royalty guarantees.

+ References

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-Name Accounting Standards Codification
-Topic 928
-SubTopic 440
-Section 50
-Paragraph 1
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Period Type:	instant

- Details

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Name:	us-gaap_TypeOfArrangementAxis=insm_LicenseAgreementWithAstrazenecaMember
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License and Other Agreements (Details) € in Millions, $ in Millions	1 Months Ended				12 Months Ended
	Oct. 31, 2016 USD ($)	Jul. 31, 2014	Feb. 28, 2014 USD ($)	Apr. 30, 2008 EUR (€)	Dec. 31, 2019 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2009 USD ($)	Dec. 31, 2004 USD ($)	Oct. 31, 2017 USD ($)	Sep. 30, 2015 USD ($)
PARI Agreement
Collaboration Agreements
Initial term of contract manufacturing agreement		15 years
Additional term of contract manufacturing agreement		5 years
PARI Agreement \| Maximum
Collaboration Agreements
Future milestone payments \| €				€ 0.5
PARI Agreement \| Minimum
Collaboration Agreements
Written notice period required for termination of contract manufacturing agreement		1 year
CFFT
Collaboration Agreements
Compensation earned under research funding agreements with CFFT							$ 2.2	$ 1.7
Royalty payable on approval of ARIKAYCE as commercialized drug					$ 13.4
Period for meeting sales milestones for additional royalty payments					5 years
Royalty payable on meeting certain sales milestones					$ 3.9
Therapure
Collaboration Agreements
Initial term of contract manufacturing agreement			5 years
Period of each automatic renewal of contract manufacturing agreement			2 years
Written notice period required for termination of contract manufacturing agreement			2 years
Minimum obligation			$ 6.0
Fill/Finish Agreement
Collaboration Agreements
Minimum obligation										$ 2.7
Period prior to expiration for extension					1 year
License Agreement with AstraZeneca
Collaboration Agreements
Royalty payment	$ 35.0
License Agreement with AstraZeneca \| Research and development expenses
Collaboration Agreements
Upfront payment						$ 30.0
License Agreement with AstraZeneca \| Maximum
Collaboration Agreements
Aggregate payment upon the achievement of certain clinical milestones	85.0
Additional contingent payments upon second indication to develop INS1007	42.5
Supply Agreement with Patheon UK Limited
Collaboration Agreements
Agreement to purchase raw materials and fixed assets									$ 60.0
License and Service \| License Agreement with AstraZeneca
Collaboration Agreements
Annual net sales	$ 1,000.0
Milestone, New Drug Application \| PARI Agreement
Collaboration Agreements
PARI milestone upon FDA approval \| €				1.0
Milestone, FDA Approval \| PARI Agreement
Collaboration Agreements
PARI milestone upon FDA approval \| €				€ 1.5