Sales and advertising expense (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Sales and advertising expense
Employee benefits expense - Sales and advertising	€ 8,183	€ 5,830	€ 5,125
Sales and advertising campaigns	47,836	40,186	31,819
Sales and advertising expense	€ 56,019	€ 46,016	€ 36,944

The amount of expense relating to the marketing and selling of goods or services.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 85
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_85&doctype=Standard
-URIDate 2019-03-27

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