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

No definition available.

Name:	opht_AggregateRoyaltyGuaranteesCommitmentsAmount
Namespace Prefix:	opht_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Gain On Extinguishment Of Royalty Liability

+ References

No definition available.

+ Details

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Namespace Prefix:	opht_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of tranches in financing.

+ References

No definition available.

+ Details

Name:	opht_NumberOfTranchesInFinancing
Namespace Prefix:	opht_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cash inflow from debt classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

Name:	us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=opht_FovistaAndRelatedProductsAndOtherProductsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Financing Agreement with Novo Holdings A/S (Details)	1 Months Ended			12 Months Ended			19 Months Ended
Financing Agreement with Novo Holdings A/S (Details)	Nov. 30, 2014 USD ($)	Jan. 31, 2014 USD ($)	May 31, 2013 USD ($) tranche	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Nov. 30, 2014 USD ($)
Agreement
Gain on extinguishment of Royalty Purchase Liability				$ 0	$ 0	$ 125,000,000
Novo A/S \| Novo Agreement \| Fovista, Fovista-Related Products, and Other Products
Agreement
Number of tranches in financing \| tranche			3
Aggregate royalty rights			$ 125,000,000.0
Proceeds from royalty purchase agreement	$ 41,700,000	$ 41,700,000	41,700,000				$ 125,000,000.0
Royalty purchase liability			$ 125,000,000.0