Sales and advertising expense (Details) - EUR (€) € in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Sales and advertising expense
Employee benefits expense - Sales and advertising	€ 1,955	€ 1,950	€ 6,548	€ 5,763
Sales and advertising campaigns	4,235	11,825	15,736	34,766
Sales and advertising expense	€ 6,190	€ 13,775	€ 22,284	€ 40,529

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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