Number of warrants into which each share may be converted.

No definition available.

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Period Type:	instant

- Definition

Class of Warrant or Right, Number of Warrants Issued

+ References

No definition available.

+ Details

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Namespace Prefix:	mtva_
Data Type:	xbrli:sharesItemType
Balance Type:	na
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- Definition

Number of warrants or rights outstanding and exercisable.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Number of warrants exchanged for the securities called by warrants.

+ References

No definition available.

+ Details

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Namespace Prefix:	mtva_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of warrants exercised for the securities.

+ References

No definition available.

+ Details

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Namespace Prefix:	mtva_
Data Type:	xbrli:sharesItemType
Balance Type:	na
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- Definition

The period from date of stockholders approval considered for warrants expiry term.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The threshold period following the public announcement of the Company receiving positive Phase 1 multiple ascending dose ("MAD") data for expiry of warrants.

+ References

No definition available.

+ Details

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Namespace Prefix:	mtva_
Data Type:	xbrli:durationItemType
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
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

+ Details

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

+ Details

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

- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

+ Details

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

- Definition

Period between issuance and expiration 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 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

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- Details

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Stockholders equity - Warrants - Narrative (Details) - USD ($)		1 Months Ended		3 Months Ended	12 Months Ended
	Nov. 30, 2022	Jun. 30, 2024	Nov. 30, 2022	Sep. 30, 2024	Dec. 31, 2024	Oct. 31, 2022
Proceeds from exercise of warrants					$ 1,000
Warrants term					2 years
November 2022 Series A and B
Outstanding and exercisable warrants					1,423,504
Proceeds from exercise of warrants			$ 0
Exercise Price	$ 0		$ 0
June 2024 Series A
Exercise Price					$ 3.93
Expired terms					12 months
Threshold period following the public announcement of receiving positive phase 1 multiple ascending dose data for expiry of warrants					60 days
June 2024 Series B
Exercise Price					$ 3.93
Expired terms					5 years
Threshold period following the public announcement of receiving positive phase 1 multiple ascending dose data for expiry of warrants					6 months
Series A warrant
Number of warrants exchanged					6,768,837
Warrants to purchase shares of common stock					846,105
Threshold period following the public announcement of receiving positive phase 1 multiple ascending dose data for expiry of warrants		60 days
November 2022 Series B
Number of warrants exchanged					8
Exercised warrants					8
Proceeds from exercise of warrants					$ 0
Exercise Price	$ 0		$ 0		$ 0	$ 3
Number of warrants	6,843,666
Warrants to purchase shares of common stock	855,458		855,458
Pre-Funded Warrants
Pre-Funded warrants issued				351,171