Business Combinations - Summary of Post Acquisition Impact (Detail) - Post acquisition impact [member] - Continuing operations [member] - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of detailed information about business combination [line items]
Revenue	€ 204	€ 1,202	€ 505
Profit/(loss) before tax for the financial year	€ 2	€ 145	€ (1)

The amount of revenue of the acquiree since the acquisition date included in the consolidated statement of comprehensive income. [Refer: Revenue]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2019-01-01
-Paragraph B64
-Subparagraph q
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2019-en-r&anchor=para_B64_q_i&doctype=Appendix&subtype=B
-URIDate 2019-03-27

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration