Additional contingent payable upon satisfaction of certain criteria during the period.

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- Definition

The revenues from collaborative research and development activities. Collaboration revenue, which is earned under agreements with third parties for research and development activities, may include nonrefundable upfront payments, cost reimbursements and milestone payments.

+ References

No definition available.

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Future milestone payments at the balance sheet date.

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No definition available.

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minimum annual royalty milestone payments at the balance sheet date.

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No definition available.

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The minimum annual royalty payments payable until first commercial sale.

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No definition available.

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The amount of non-refundable upfront payment received with related to the collaborative agreement.

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No definition available.

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The amount of milestone payment achieved during the period for collaboration arrangement.

+ References

No definition available.

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The amount of potential milestone payments consideration recognized during the period for collaboration arrangement.

+ References

No definition available.

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- Definition

Revenue derived from research and development services during the period.

+ References

No definition available.

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets 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 SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

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Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-Subparagraph (SX 210.5-03.1(e))

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- Definition

Costs incurred and are directly related to generating maintenance revenues. Also includes cost of maintenance on client contracts.

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-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph (SX 210.5-03.2(e))

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The cash outflows from the purchase of net carrying value allocated to in-process research and development costs and materials acquired in a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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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.

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 1

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-Section 50

-Paragraph 1

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Collaborations (Details Textual) (USD $)	1 Months Ended			3 Months Ended								12 Months Ended			1 Months Ended
Collaborations (Details Textual) (USD $)	Jul. 31, 2014	Apr. 30, 2012	Feb. 28, 2011	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Aug. 31, 2013	Dec. 31, 2009	Dec. 31, 1995
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable Upfront Payments Received		$ 120,000,000
Collaboration Revenue												70,353,483ecyt_CollaborationRevenue	64,870,919ecyt_CollaborationRevenue	34,682,111ecyt_CollaborationRevenue
Research and Development Expense	2,200,000us-gaap_ResearchAndDevelopmentExpense		300,000us-gaap_ResearchAndDevelopmentExpense	3,998us-gaap_ResearchAndDevelopmentExpense	5,675us-gaap_ResearchAndDevelopmentExpense	18,990us-gaap_ResearchAndDevelopmentExpense	12,987us-gaap_ResearchAndDevelopmentExpense	13,533us-gaap_ResearchAndDevelopmentExpense	13,501us-gaap_ResearchAndDevelopmentExpense	18,607us-gaap_ResearchAndDevelopmentExpense	12,259us-gaap_ResearchAndDevelopmentExpense	41,649,389us-gaap_ResearchAndDevelopmentExpense	57,898,971us-gaap_ResearchAndDevelopmentExpense	35,670,418us-gaap_ResearchAndDevelopmentExpense
Deferred Revenue								59,700,000us-gaap_DeferredRevenue					59,700,000us-gaap_DeferredRevenue
Licenses Revenue												52,700,000us-gaap_LicensesRevenue	51,500,000us-gaap_LicensesRevenue
License and Services Revenue												17,600,000	13,400,000
Additional Contingent Payable Upon Satisfaction Of Certain Criteria				5,900,000								5,900,000
Minimum Annual Royalty Payments Payable Until First Commercial Sale																	12,500
Maintenance Costs			25,000us-gaap_MaintenanceCosts
Payments to Acquire in Process Research and Development		120,000,000
Future Milestone Payments																500,000ecyt_FutureMilestonePayments
Royalty Agreements [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Minimum Annual Royalty Payments Payable Until First Commercial Sale																15,000
Minimum Annual Royalty Milestone Payments																100,000
Proceed Trial Termination [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Research and Development Expense												1,100,000
NMP [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable Upfront Payments Received															1,000,000
Deferred Revenue				900,000								900,000
Potential Milestone Payments												4,500,000			4,500,000
Merck [Member] \| Proceed Trial Termination [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Research and Development Expense												500,000
Good Laboratory Practice [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Payment for Milestone Achieved												50,000
PSMA tubulysin [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Payment for Milestone Achieved												100,000
Folate Tubulysin [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Payment for Milestone Achieved													100,000
Development Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable Upfront Payments Received		5,000,000
Non Substantive Milestone [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable Upfront Payments Received		$ 5,000,000