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

Adjustment to the amount of discount used to measure fair value for lack of ability to convert business interests into cash quickly..

No definition available.

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

Represents the additional milestone payments to be made under the license agreement.

No definition available.

Name:	incy_LicenseAgreementAdditionalMilestonePayments
Namespace Prefix:	incy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the target selection and option exercise fee payments to be made under the license agreement.

No definition available.

Name:	incy_LicenseAgreementTargetSelectionAndOptionExerciseFeePayments
Namespace Prefix:	incy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

No definition available.

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

Represents the number of program targets identified.

No definition available.

Name:	incy_NumberOfProgramTargets
Namespace Prefix:	incy_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the purchase of common stock under Stock Purchase Agreement.

No definition available.

Name:	incy_PurchaseOfCommonStockUnderStockPurchaseAgreementInShares
Namespace Prefix:	incy_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Represents the period of time that the company will not sell or otherwise transfer any of the equity method shares.

No definition available.

Name:	incy_StockPurchaseAgreementLockUpPeriod
Namespace Prefix:	incy_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Fair value of the entity's equity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

Name:	us-gaap_EquityFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_EquityMethodInvestmentAggregateCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

Name:	us-gaap_LongTermInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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.

No definition available.

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

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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

Price of a single share of a number of saleable stocks of a company.

No definition available.

Name:	us-gaap_SharePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

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

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=incy_StockPurchaseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=incy_AmendedStockPurchaseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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