Notes to the statement of financial position - Cash and cash equivalents narrative (Details) - EUR (€) € in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Subclassifications of assets, liabilities and equities [abstract]
Cash and cash equivalents	€ 60,272	€ 73,907	€ 65,261	€ 70,544
Bank balances and cash on hand	59,648	73,895
Checks	€ 624	€ 12

The amount of cash on hand and demand deposits. [Refer: Cash on hand]

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The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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