The amount of cash consideration agreed under the asset purchase agreement.

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Number Of Series Of Warrants Issued

+ References

No definition available.

+ Details

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- Definition

Percentage of asset purchase agreement that the purchase price increases per month between October 31, 2019 and the closing date if agreement is not terminated.

+ References

No definition available.

+ Details

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Balance Type:	na
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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

Sale of Stock And Issuance Of Warrants, Consideration Received Per Transaction

+ References

No definition available.

+ Details

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Namespace Prefix:	ocgn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Fair value portion of assets classified as held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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

- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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Namespace Prefix:
Data Type:	na
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- Details

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- Details

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Merger and Financing (Details) shares in Millions, $ in Millions	Oct. 31, 2019 USD ($)	Oct. 04, 2019 USD ($) series shares	May 08, 2019 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2019 shares
Reverse Merger and Financing
Number of series of warrants issued \| series		3
Histogenics
Reverse Merger and Financing
Asset purchase agreement, cash consideration	$ 7.0		$ 6.5
Percentage of increase in purchase price of asset per month (in percentage)	10.00%
Histogenics \| Level 2
Reverse Merger and Financing
Quoted price of assets held for sale of NeoCart				$ 7.0
Financing SPA
Reverse Merger and Financing
Shares issued (in shares) \| shares		2.2			2.2
Aggregate purchase price		$ 25.0