Represents the amount of the milestone payment made under the license agreement.

No definition available.

Name:	incy_LicenseAgreementMilestonePaymentAmountPaid
Namespace Prefix:	incy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents reimbursable costs pertaining to license agreements.

+ References

No definition available.

+ Details

Name:	incy_LicenseAgreementReimbursableCosts
Namespace Prefix:	incy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents reimbursed costs pertaining to research and development expenses.

+ References

No definition available.

+ Details

Name:	incy_LicenseAgreementResearchAndDevelopmentReimbursedCost
Namespace Prefix:	incy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the upfront and immediate milestone payment received under the license agreement.

+ References

No definition available.

+ Details

Name:	incy_LicenseAgreementUpfrontPaymentAndImmediateMilestonePaymentToBeReceived
Namespace Prefix:	incy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the number of clinical-stage product candidates .

+ References

No definition available.

+ Details

Name:	incy_NumberOfProductCandidates
Namespace Prefix:	incy_
Data Type:	xbrli:integerItemType
Balance Type:	na
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_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_TypeOfArrangementAxis=incy_InnoventBiologicsIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	incy_AchievementOfMilestoneAxis=incy_RegulatoryMilestonesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	incy_AchievementOfMilestoneAxis=incy_DevelopmentAndRegulatoryMilestonesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	incy_AchievementOfMilestoneAxis=incy_CommercializationMilestonesMember
Namespace Prefix:
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License agreements - Innovent (Details) - Innovent $ in Millions	1 Months Ended			12 Months Ended
	Jun. 30, 2019 USD ($)	Jan. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) item	Dec. 31, 2019 USD ($)
License agreements
Upfront and immediate milestone payment to be received under license agreement		$ 40.0
Research and development expenses reimbursed				$ 6.2
Reimbursable costs included in accounts receivable				$ 3.0
Product candidates \| item			3
Regulatory Milestones
License agreements
Milestone payment made under license agreement	$ 20.0
Regulatory Milestones \| Maximum
License agreements
Upfront and immediate milestone payment to be received under license agreement			$ 20.0
Development and Regulatory Milestones \| Maximum
License agreements
Upfront and immediate milestone payment to be received under license agreement			129.0
Commercialization Milestones \| Maximum
License agreements
Upfront and immediate milestone payment to be received under license agreement			$ 202.5