No definition available.

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Namespace Prefix:	erna_
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Period Type:	duration

- Definition

Percentage of obligated to payments of the option fees.

+ References

No definition available.

+ Details

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Namespace Prefix:	erna_
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Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from cell line customization activities.

+ References

No definition available.

+ Details

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

- Definition

The cash inflow from exclusive option and license agreement as a non-refundable up-front payment.

+ References

No definition available.

+ Details

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

- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from contract modification which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-10

+ Details

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

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-8

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12A

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

+ Details

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

- Details

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- Details

Name:	us-gaap_TimingOfTransferOfGoodOrServiceAxis=us-gaap_TransferredOverTimeMember
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CONTRACT WITH CUSTOMER (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
CONTRACT WITH CUSTOMER (Details) - USD ($) $ in Thousands	Feb. 21, 2023	Sep. 30, 2023	Sep. 30, 2023
Contract with Customers [Abstract]
Proceeds from option and license agreement	$ 300
Performance obligation, percentage	100.00%
Revenue recognized in previous periods		$ 0	$ 0
Catch-up adjustment to revenue		0	$ 0
Proceeds from cell line customization activities		400
Option fee obligation payment percentage			20.00%
Maximum [Member]
Contract with Customers [Abstract]
Revenue recognized		$ 100	$ 100
Revenue Recognized Over Time [Member]
Contract with Customers [Abstract]
Revenue recognized			$ 400