Financial Assets and Liabilities - Summary of Marketable securities (Detail) - EUR (€) € in Thousands	Mar. 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	84,460	290,688
Financial assets	610,326	758,741
Financial assets at amortised cost, class [member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	84,460	298,180
Non-current financial marketable securities	0	7,492
Current financial marketable securities	84,460	290,688
Financial assets	84,460	298,180
Financial assets at amortised cost, class [member] \| High Grade [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial assets	51,052	203,530
Financial assets at amortised cost, class [member] \| Upper Medium Grade [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial assets	33,408	94,650
Financial assets at amortised cost, class [member] \| Fixed interest rate [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial assets	75,834	205,825
Financial assets at amortised cost, class [member] \| Floating interest rate [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial assets	8,626	11,787
Financial assets at amortised cost, class [member] \| Zero Coupon [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial assets	0	80,568
Financial assets at amortised cost, class [member] \| US Treasury bills [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	0	79,086
Financial assets at amortised cost, class [member] \| US Government Bonds [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	42,955	99,337
Financial assets at amortised cost, class [member] \| Corporate bonds [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	36,907	104,236
Financial assets at amortised cost, class [member] \| Agency bonds [Member]
Disclosure Detailed Information About Marketable Securities [Line Items]
Financial marketable securities	€ 4,598	€ 15,521

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- Definition

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

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

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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]

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

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