The amount of accumulated realized loss on sale of shares.

No definition available.

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Namespace Prefix:	afmd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

It represents the value of original acquisition price of shares.

+ References

No definition available.

+ Details

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

- Definition

Represents the average selling price per share.

+ References

No definition available.

+ Details

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

- Definition

The amount of investments in equity instruments that the entity has designated at fair value through other comprehensive income Outstanding. [Refer: At fair value [member]; Other comprehensive income]

+ References

No definition available.

+ Details

Name:	afmd_FairValueOfInvestmentsInEquityInstrumentsDesignatedAsMeasuredAtFairValueThroughOtherComprehensiveIncomeOutstanding
Namespace Prefix:	afmd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of net proceeds from sale of shares.

+ References

No definition available.

+ Details

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

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

The amount of investments in equity instruments that the entity has designated at fair value through other comprehensive income. [Refer: At fair value [member]; Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 11A
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_11A_c&doctype=Standard
-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 8
-Subparagraph h
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_8_h&doctype=Standard
-URIDate 2023-03-23

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfFinancialAssetsAxis=afmd_CommonSharesRoivantSciencesLtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_CounterpartiesAxis=afmd_AmphivenaMember
Namespace Prefix:
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Long-term financial assets (Details) € / shares in Units, $ / shares in Units, € in Thousands, $ in Millions	1 Months Ended		12 Months Ended
	Jun. 30, 2022 EUR (€) € / shares	Jun. 30, 2022 USD ($) $ / shares	Dec. 31, 2022 EUR (€)	Dec. 31, 2023 EUR (€)
Preferred Shares
Long-term financial assets
Fair value shares of remaining			€ 0	€ 0
Common Shares Roivant Sciences Ltd
Long-term financial assets
Weighted average selling price \| (per share)	€ 4.54	$ 4.59
Gross proceeds from sale	€ 6,300	$ 6.4
Cumulated loss on sale			10,800
Acquisition price of shares			€ 17,100
Amphivena \| Preferred Shares
Long-term financial assets
Fair value of shares				€ 0