Class of warrant or right issued exercisable for shares of common stock.

No definition available.

Name:	isco_ClassOfWarrantOrRightIssuedExercisableForSharesOfCommonStock
Namespace Prefix:	isco_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_ClassOfWarrantOrRightOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Expiration date of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=isco_OctoberTwoThousandFourteenFinancingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=isco_MarchTwoThousandSixteenFinancingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Stockholders' Deficit - Common Stock Warrants - Additional Information (Detail) - $ / shares	1 Months Ended
	Mar. 31, 2016	Oct. 31, 2014	Dec. 31, 2020
Class Of Warrant Or Right [Line Items]
Warrants issued exercisable for shares of common stock	11,159,995	62,047
Exercise price of warrants	$ 1.75	$ 1.75
October 2014 [Member]
Class Of Warrant Or Right [Line Items]
Common stock warrants issued expiration date			Apr. 30, 2020
March 2016 [Member]
Class Of Warrant Or Right [Line Items]
Common stock warrants issued expiration date			Mar. 15, 2021
Common stock warrants outstanding			3,948,569