Additional cancellation of contingently recoverable commercialization losses.

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Calendar year net sales threshold for increase in royalty rate.

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Cancellation of contingently recoverable accumulated commercialization losses.

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Collaborative Agreements And Contracts [Line Items]

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Contingently recoverable accumulated commercialization losses.

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License Agreement Start Year Month

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License Option Exercise Upfront Payment

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Maximum percentage of quarterly profit sharing offset by previously incurred and unapplied pre profitability net losses.

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Non royalty consideration percentage.

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Number of countries in which lead product received regulatory approval.

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Option period to acquire license.

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Percentage of royalty offsetting.

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Proceeds from earned profit share and collaborative research and development revenue.

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Proceeds received from earned sales-based royalties.

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Profit Sharing on Sale of Product Minimum Percentage After Maximum Allowable Offset of Previously Incurred and Unapplied Pre Profitability Net Losses.

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No definition available.

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Profit sharing on sale of product percentage.

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Royalty income and collaborative research and development revenue.

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Royalty percentage earned from sales of product

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Royalty Rate Percentage

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- Definition

Share percentage of pre-profitability net losses on sale of product.

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Upfront Cash Payment Received Under Collaboration Agreement

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Upfront cash payment received under license agreement.

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Amount, after allowance, receivable from customers, clients, or other third-parties, and receivables classified as other due within one year or the normal operating cycle, if longer.

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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.

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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 from multiple-deliverable arrangements that include licensing fees and maintenance revenue. Licensing revenue is 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. Maintenance revenue is derived from maintenance services provided under contracts or arrangements with clients. Services may include the maintenance of software, plant and equipment, and facilities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Revenue from multiple-deliverable arrangements that include licensing fees and services revenue. Licensing revenue is 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. Services revenue may be derived by providing other, nonspecified, services during the reporting period.

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Represents the value established as the selling price of the significant unit of accounting used to allocate the consideration of the multiple-deliverable arrangement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

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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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License and Collaboration Agreements - Additional Information (Detail)						1 Months Ended			3 Months Ended				6 Months Ended
	Jan. 01, 2021	Jan. 01, 2020 USD ($)	Jan. 01, 2019 USD ($)	Jul. 10, 2017 USD ($)	Oct. 25, 2016 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2013 USD ($)	Jun. 30, 2011 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2017 USD ($) Country	Dec. 31, 2016 USD ($)	Jun. 30, 2017 USD ($)
Collaborative Agreements And Contracts [Line Items]
Collaborative research and development revenue									$ 461,000		$ 5,702,000		$ 601,000	$ 5,736,000
Royalty income									472,000		269,000		717,000	$ 512,000
Accounts receivable						$ 288,000			288,000				$ 288,000		$ 251,000
ILUVIEN [Member] \| Europe [Member]
Collaborative Agreements And Contracts [Line Items]
Number of countries in which lead product received regulatory approval \| Country													17
Prior Alimera Agreement [Member]
Collaborative Agreements And Contracts [Line Items]
Percentage of company's share of net profits														20.00%
Pre-profitability net losses percentage														20.00%
Maximum percentage offset of current period net profits against previously incurred and unapplied pre-profitability quarterly net losses														4.00%
Percentage of net profit share after offset of previously incurred and unapplied pre-profitability net losses														16.00%
Percentage of royalties received from sublicense														20.00%
Percentage of non-royalty consideration received from sublicense														33.00%
Amount received, profit share from sale of licensed products										$ 50,000
Amended Alimera Agreement [Member]
Collaborative Agreements And Contracts [Line Items]
Royalty percentage earned from sales of product													2.00%
Contingently recoverable accumulated commercialization losses				$ 25,000,000
Partial cancellation of contingently recoverable accumulated commercialization losses in lieu of upfront license fee				$ 10,000,000
Proceeds received from earned sales-based royalties									196,000				$ 196,000
Amended Alimera Agreement [Member] \| Scenario, Forecast [Member]
Collaborative Agreements And Contracts [Line Items]
Calendar year net sales threshold for increase in royalty rate			$ 75,000,000
Royalty percentage offset for amounts earned above 2% to be applied against balance of accumulated commercialization losses	20.00%		50.00%
Additional cancellation of contingently recoverable commercialization losses		$ 5,000,000
Amended Alimera Agreement [Member] \| Scenario, Forecast [Member] \| Minimum [Member]
Collaborative Agreements And Contracts [Line Items]
Royalty percentage earned from sales of product			6.00%
Amended Alimera Agreement [Member] \| Scenario, Forecast [Member] \| Maximum [Member]
Collaborative Agreements And Contracts [Line Items]
Royalty percentage earned from sales of product			8.00%
Pfizer Collaboration Agreement [Member]
Collaborative Agreements And Contracts [Line Items]
Upfront cash payment received under collaboration agreement								$ 2,300,000
Estimated selling price of the deliverables for revenue recognition								$ 6,700,000
Collaborative research and development revenue											5,600,000	$ 0
Option period to acquire license					60 days
License option upfront payment upon exercise					$ 10,000,000
Bausch and Lomb [Member]
Collaborative Agreements And Contracts [Line Items]
Royalty income									276,000		269,000		521,000	$ 512,000
Accounts receivable						277,000			277,000				$ 277,000		246,000
OncoSil Medical UK Limited [Member]
Collaborative Agreements And Contracts [Line Items]
Percentage of non-royalty consideration received from sublicense													20.00%
Royalty percentage earned from sales of product													8.00%
Collaborative research and development revenue									100,000		100,000		$ 100,000	100,000
License agreement commencement date													2012-12
Receipt of upfront license fee							$ 100,000
Payment of annual license maintenance fee						100,000
Deferred revenue						0			0				$ 0
Feasibility Study Agreement [Member]
Collaborative Agreements And Contracts [Line Items]
Upfront cash payment received under collaboration agreement									850,000
Collaborative research and development revenue									355,000		3,000		405,000	11,000
Deferred revenue						$ 505,000			505,000				505,000		$ 50,000
Prior Alimera Agreement and/or Amended Alimera Agreement [Member]
Collaborative Agreements And Contracts [Line Items]
Total revenues earned from Alimera									$ 200,000		$ 14,000		$ 290,000	$ 34,000