Annual report pursuant to Section 13 and 15(d)

Cover
- Cover
- Audit Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Notes Payable - Narrative (Details)

v3.23.1

Notes Payable - Narrative (Details) $ / shares in Units, $ in Thousands				1 Months Ended		3 Months Ended		12 Months Ended
	Sep. 29, 2021 USD ($)	Jul. 30, 2021 USD ($)	Jun. 04, 2021 USD ($) day $ / shares shares	Jun. 30, 2022 USD ($) $ / shares	Jan. 31, 2021 $ / shares shares	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($) $ / shares shares	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($) $ / shares
Line of Credit Facility [Line Items]
Prepayment on Notes								$ 14,806	$ 0
Exercise price per share (in dollars per share) \| $ / shares					$ 0.012				$ 0.012
Warrant
Line of Credit Facility [Line Items]
Number of shares issued (in shares) \| shares					139,747
Horizon & Powerscourt Notes \| Notes Payable
Line of Credit Facility [Line Items]
Principal amount			$ 35,000
Proceeds from debt	$ 5,000	$ 10,000	$ 20,000			$ 15,000
Prepayment on Notes				$ 15,000			$ 15,000
Repayment of debt, principal				$ 14,800
Total principal payments1						$ 21,244		$ 21,244	$ 36,050
Debt instrument, term			42 months
Interest rate			6.25%
Interest-only payment period			18 months
Interest-only payment extension period			24 months
Number of business days required for prepayment \| day			10
Prepayment charges percentage			3.00%
Additional final payment percentage			3.00%			3.00%		3.00%
Proceeds from issuance of warrants			$ 900
Debt issuance costs incurred									2,100
Debt instrument, final payment fee						$ 1,100		$ 1,100	$ 1,100
Effective rate									20.70%
Horizon & Powerscourt Notes \| Notes Payable \| Warrant
Line of Credit Facility [Line Items]
Number of shares issued (in shares) \| shares			33,656				33,656
Exercise price per share (in dollars per share) \| $ / shares			$ 31.20	$ 31.20			$ 31.20
Warrants or rights exercisable term			10 years				10 years
Horizon & Powerscourt Notes \| Notes Payable \| Prime Rate
Line of Credit Facility [Line Items]
Floor interest rate			3.25%

- Definition

Class of Warrant Or Right, Warrants Or Rights Exercisable, Term

+ References

No definition available.

+ Details

Name:	avtx_ClassOfWarrantOrRightWarrantsOrRightsExercisableTerm
Namespace Prefix:	avtx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Accrued And Unpaid Interest, Subject to Prepayment Charges, Percentage

+ References

No definition available.

+ Details

Name:	avtx_DebtInstrumentAccruedAndUnpaidInterestSubjectToPrepaymentChargesPercentage
Namespace Prefix:	avtx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Additional Final Payment, Percentage

+ References

No definition available.

+ Details

Name:	avtx_DebtInstrumentAdditionalFinalPaymentPercentage
Namespace Prefix:	avtx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Final Payment Fee

+ References

No definition available.

+ Details

Name:	avtx_DebtInstrumentFinalPaymentFee
Namespace Prefix:	avtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Interest Only Payment Extension Period

+ References

No definition available.

+ Details

Name:	avtx_DebtInstrumentInterestOnlyPaymentExtensionPeriod
Namespace Prefix:	avtx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Interest Only Payment Period

+ References

No definition available.

+ Details

Name:	avtx_DebtInstrumentInterestOnlyPaymentPeriod
Namespace Prefix:	avtx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Interest Rate, Floor

+ References

No definition available.

+ Details

Name:	avtx_DebtInstrumentInterestRateFloor
Namespace Prefix:	avtx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Number of Business Days Required for Prepayment

+ References

No definition available.

+ Details

Name:	avtx_DebtInstrumentNumberOfBusinessDaysRequiredForPrepayment
Namespace Prefix:	avtx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Repayment Of Debt, Principal

+ References

No definition available.

+ Details

Name:	avtx_RepaymentOfDebtPrincipal
Namespace Prefix:	avtx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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 https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644

+ Details

Name:	us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

Reference 3: 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(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI https://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI https://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466204&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227

+ Details

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

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

+ Details

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

- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

+ Details

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

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585

+ Details

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

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=avtx_HorizonPowerscourtNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LoansPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: