The amount the entity has committed to make for aggregate future royalty guarantees under agreement.

No definition available.

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- Definition

Financing Agreement, Number of Purchases

+ References

No definition available.

+ Details

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- Definition

The number of tranches in financing.

+ References

No definition available.

+ Details

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Namespace Prefix:	opht_
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- Definition

Amount of cash inflow from debt classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

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- 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

The amount the entity has committed to make for future royalty guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 440
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473578&loc=d3e63223-108013

+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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Financing Agreement with Novo A/S (Details)	1 Months Ended			19 Months Ended
Financing Agreement with Novo A/S (Details)	Nov. 30, 2014 USD ($)	Jan. 31, 2014 USD ($)	May 31, 2013 USD ($) tranche purchase	Nov. 30, 2014 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty purchase liability					$ 125,000,000	$ 125,000,000
Novo A/S \| Novo Agreement \| Fovista, Fovista-Related Products, and Other Products
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Number of tranches in financing (in tranche) \| tranche			3
Aggregate royalty rights			$ 125,000,000.0
Number of separate purchases provided for in financing agreement \| purchase			3
Proceeds from royalty purchase agreement	$ 41,700,000	$ 41,700,000	$ 41,700,000	$ 125,000,000
Royalty purchase liability			$ 125,000,000