The fair value, at the acquisition date, of equity interests of the acquirer transferred as consideration in a business combination. [Refer: Business combinations [member]]

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The amount recognised as of the acquisition date for net identifiable assets acquired or liabilities assumed in a business combination. [Refer: Business combinations [member]]

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The nominal value per share.

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Share listing expense and change in fair value of warrant liabilities - Additional Information (Detail) € / shares in Units, € in Thousands	12 Months Ended
	Dec. 31, 2020 EUR (€) shares Warrants € / shares	Dec. 31, 2019 EUR (€)	Dec. 31, 2018 EUR (€)	Jul. 01, 2020 EUR (€) shares Warrants € / shares	Jul. 01, 2020 $ / shares
Disclosure of share listing expense [line items]
Closing price of ARYA ordinary shares \| € / shares	€ 0.01
Expense on the closing date	€ 152,787
Gains losses on financial liabilities at fair value through profit or loss	17,775
Financial liabilities	28,946	€ 8,370
ARYA [member]
Disclosure of share listing expense [line items]
Fair value of ARYA ordinary shares and warrants	243,100
Closing price of ARYA ordinary shares \| $ / shares					$ 15.15
Identifiable net assets	90,284			€ 90,300
Expense on the closing date	€ 152,787
Warrants [member]
Disclosure of share listing expense [line items]
Closing price of ARYA public warrants \| € / shares	€ 2.35			€ 4.82
Warrants [member] \| ARYA [member]
Disclosure of share listing expense [line items]
Fair value of ARYA ordinary shares and warrants	€ 34,644
ARYA Shares \| Warrants	7,187,500			7,187,500
Closing price of ARYA public warrants \| € / shares	€ 4.82
Financial liabilities	€ 34,400
Ordinary shares [member]
Disclosure of share listing expense [line items]
Closing price of ARYA ordinary shares \| € / shares				€ 0.01
Ordinary shares [member] \| ARYA [member]
Disclosure of share listing expense [line items]
Fair value of ARYA ordinary shares and warrants	€ 243,071
Closing price of ARYA ordinary shares \| € / shares	€ 13.53
ARYA Shares \| shares	17,968,750			17,968,750