Financial Risk Management - Summary of Marketable securities (Detail) - EUR (€) € in Thousands	Dec. 31, 2023	Dec. 31, 2022
Disclosure Detailed Information About Marketable Securities [Line Items]
Non-current financial marketable securities	€ 0	€ 7,492
Current financial marketable securities	7,275	290,688
Financial assets at amortised cost, class [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	7,275	298,180
Financial assets at amortised cost, class [member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	7,275	298,180
Non-current financial marketable securities		7,492
Current financial marketable securities	7,275	290,688
Financial assets at amortised cost, class [member] \| US Treasury bills [Member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	4,523	79,086
Financial assets at amortised cost, class [member] \| US Government Bonds [Member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities		99,337
Financial assets at amortised cost, class [member] \| Corporate bonds [Member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	2,752	104,236
Financial assets at amortised cost, class [member] \| Agency bonds [Member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities		15,521
Financial assets at fair value, class [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	7,266	295,843
Financial assets at fair value, class [member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	7,266	295,843
Non-current financial marketable securities		7,201
Current financial marketable securities	7,266	288,642
Financial assets at fair value, class [member] \| US Treasury bills [Member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	4,519	79,043
Financial assets at fair value, class [member] \| US Government Bonds [Member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities		98,075
Financial assets at fair value, class [member] \| Corporate bonds [Member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	€ 2,747	103,301
Financial assets at fair value, class [member] \| Agency bonds [Member] \| Liquidity risk [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities		€ 15,424

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- Definition

The amount of current financial assets available-for-sale. [Refer: Financial assets available-for-sale; Current financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2023-01-01
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 8
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_8_d&doctype=Standard&book=b
-URIDate 2022-03-24

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- Definition

The amount of non-derivative financial assets that are designated as available for sale or are not classified as (a) loans and receivables; (b) held-to-maturity investments; or (c) financial assets at fair value through profit or loss. [Refer: Derivative financial assets; Financial assets at fair value through profit or loss; Held-to-maturity investments]

+ References

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The amount of non-current financial assets available-for-sale. [Refer: Financial assets available-for-sale; Non-current financial assets]

+ References

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