Net exchange rate gains/(losses) - Schedule of Net Exchange Rate Gains (Losses) (Detail) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of net exchange rate gains losses [abstract]
Net realised gains/(losses) on derivative instruments	€ (737)	€ (906)	€ 1,912
Net realised gains/(losses) on trade receivables and payables	1,600	3,353	445
Total net realised gains (a)	863	2,447	2,357
Net unrealised gains/(losses) on derivative instruments	(638)	(57)	943
Net unrealised gains/(losses) on trade receivables and payables	(531)	(5,437)	(48)
Net unrealised gains/(losses) on non-monetary assets	(2,034)	(867)	(2,219)
Total net unrealised losses (b)	(3,203)	(6,361)	(1,324)
Total realised and unrealised exchange rate gains/(losses) (a+b)	€ (2,340)	€ (3,914)	€ 1,033

The amount of exchange differences recognised in profit or loss that arise from foreign currency transactions, excluding those arising on financial instruments measured at fair value through profit or loss in accordance with IFRS 9. [Refer: At fair value [member]; Financial instruments, class [member]]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2019-01-01
-Section A Statement of cash flows for an entity other than a financial institution
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&doctype=Illustrative%20Examples&dita_xref=IAS07_IE_A_TI
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 21
-IssueDate 2019-01-01
-Paragraph 52
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=21&code=ifrs-tx-2019-en-r&anchor=para_52_a&doctype=Standard
-URIDate 2019-03-27

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