Property and Equipment (Details) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($) ft²
Property and Equipment
Property and Equipment, gross	$ 131,269	$ 116,464
Less accumulated depreciation and amortization	(45,263)	(34,674)
Property and Equipment, net	86,006	81,790
Area of laboratory and office building on lease (in square feet) \| ft²			190,000
Term of lease			15 years
Minimum monthly lease rental	$ 500
Initial term of lease over which minimum lease rent is required to be payable	10 years
Last term of lease	5 years
Letter of credit for posted for lease facility	$ 15,000
Restricted investments related to direct financing lease	14,000	14,500
Depreciation expense including amortization expense of leasehold improvements	11,300	5,100	$ 3,200
Office Equipment
Property and Equipment
Property and Equipment, gross	6,753	6,090
Laboratory Equipment
Property and Equipment
Property and Equipment, gross	31,296	26,800
Computer Equipment
Property and Equipment
Property and Equipment, gross	22,491	18,648
Building And Leasehold Improvements
Property and Equipment
Property and Equipment, gross	$ 70,729	$ 64,926

Represents the amount of letter of credit for posted for lease facility.

No definition available.

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

- Definition

Represents the initial lease term over which lessee is obligated to make or can be required to make payment of minimum lease rental expenses.

+ References

No definition available.

+ Details

Name:	incy_OperatingLeasesInitialTermOfLeaseOverWhichSpecifiedMinimumLeaseRentalIsPayable
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- Definition

Represents the remaining lease term over which lessee is obligated to make or can be required to make payment of minimum lease rental expenses.

+ References

No definition available.

+ Details

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- Definition

Represents the area of laboratory and office building, in square feet taken on lease by the entity.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 14
-Article 5

+ Details

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

- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

Name:	us-gaap_Depreciation
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

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Namespace Prefix:	us-gaap_
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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	debit
Period Type:	instant

- 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

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Regulation S-X (SX)
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Details

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