Details of the Statements of Profit or Loss and Other Comprehensive Income (Revenues) (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of Details of Statements of Profit or Loss and Other Comprehensive Income Loss [Abstract]
Revenues from the sale of solar electricity	€ 2,577	€ 13,069	€ 12,593
Revenues from the sale of gas and power produced by anaerobic digestion plants	6,002	4,786	4,483
Revenues from concessions project	1,066	1,133	1,041
Total Revenues	€ 9,645	€ 18,988	€ 18,117

The amount of revenue arising from the sale of oil and gas products. [Refer: Revenue]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2020-01-01

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