Initial fee received from collaboration or license agreement.

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Portion of upfront fee allocated to agreement.

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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.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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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The amount of consideration recognized during the period for the milestone or milestones.

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Collaboration and Other Agreements, Takeda (Details) - USD ($)	1 Months Ended	12 Months Ended
	May 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Collaboration and Other Agreements [Line Items]
Deferred revenue included in current liabilities		$ 4,261,000	$ 5,866,000
Takeda Pharmaceutical Company Limited (Takeda) \| Takeda MGD010 Agreement
Collaboration and Other Agreements [Line Items]
Nonrefundable upfront payment	$ 15,000,000
Amount allocated to agreement	$ 10,000,000
Deferred revenue included in current liabilities			2,100,000
Expected period of development	24 months
Recognized revenue under agreement		2,100,000	8,000,000	$ 3,000,000
Milestone received			3,000,000
Deferred revenue		$ 0	2,100,000
Takeda Pharmaceutical Company Limited (Takeda) \| Research Collaboration and License Option Agreement
Collaboration and Other Agreements [Line Items]
Amount allocated to agreement	$ 5,000,000
Recognized revenue under agreement			$ 1,300,000	$ 5,000,000