Executive and Supervisory Board Compensation - Supervisory Board Compensation (Details) - Supervisory Board Members - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Executive and Supervisory Board Compensation
Total compensation	€ 3,770	€ 3,702	€ 3,663
Thereof fixed compensation	3,218	3,162	3,135
Thereof committee remuneration	€ 553	€ 540	€ 528

The amount of remuneration paid or payable to the entity's directors.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_DirectorsRemunerationExpense
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration