XML 46 R32.htm IDEA: XBRL DOCUMENT v3.22.2.2

DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION (Details)	Sep. 21, 2022 USD ($) shares	Oct. 17, 2022 $ / shares	Sep. 30, 2022 $ / shares	Dec. 31, 2021 $ / shares	Jul. 16, 2021
Description of Business [Abstract]
Common stock, par value (in dollars per share) | $ / shares		$ 0.005	$ 0.005	$ 0.005
Reverse Stock-Split [Abstract]
Stock conversion ratio	0.05
Amount paid for fractional share in connection with reverse stock split | $	$ 719
Number of fractional shares considered in reverse stock split (in shares) | shares	175
NoveCite, INC. [Member]
Description of Business [Abstract]
Percentage of total outstanding equity interests					25.00%

X

- Definition

Amount of cash outflow for fractional shares in connection with reverse stock split.

+ References

No definition available.

+ Details

Name:	erna_CashPaidForFractionalSharesInConnectionWithReverseStockSplit
Namespace Prefix:	erna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Number of shares considered as fractional in reverse stock split.

+ References

No definition available.

+ Details

Name:	erna_NumberOfSharesConsideredAsFractionalInReverseStock
Namespace Prefix:	erna_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	erna_ReverseStockSplitAbstract
Namespace Prefix:	erna_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

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

X

- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

X

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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

X

- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187143-122770

+ Details

Name:	us-gaap_StockholdersEquityNoteStockSplitConversionRatio1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=erna_NoveCiteINCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: